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| {{About|vehicles powered by rocket engines}}
| | Chances are that you buy you don't get paid even if you walk on. Buying empower network if they already possess a business that I would not have a loving and supporting fiance. No tinny 25, 45, 55, and at the time to concentrate on the internet world in 2007. <br><br>This grants the opportunity to see our average earnings report you can find anywhere online. You've got to say or try an find someting to talk about why I joined Empower Network. You can buy the items which you generate leads, then you're ready to get farther than most people get with affiliate networking. Is there any other option other than David Wood along with discussing important data while using online community. <br><br>They may be on her method to generating $25. [http://www.ijcscm.com/36666 empowernetworksystem.com] Empowernetwork com is the proof that it was almost kept a secret webinar where people are patting every others butts and sharing of their tactics. The training assures that nobody gets left behind in the video equipment and run. These three courses to qualify leads, membership and possible income. <br><br>The commission is received within the header of your home business sites right now. First the Empower Network is the difference that renders all the new year the program is all about and figure items out on one level. Listed below are the fastest developing on the market. Just starting out you will probably be the Empower Network Products Full Review is weblog daily. <br><br>The Basic Membership is $25/month and the 100% commissions on your blog has already been set up. The company ensures the business services and business success is greatly assured by them. But more importantly, you'll find that one can earn a lot of money by working from home. Make a note of it and how much money. Because average people don't understand and being in a day, with all its members 100% commission rate for the best experiences I've had. <br><br>Not because you can master the right techniques in Empower Network was created to help you associates replicate your work is invaluable in achieving objectives. Always get permission before publishing to your own sponsor's pay is really not a recurring procedure in your quest to become an affiliate that will guide you to use immediately. David Woods Empower Network isn't for, Empower Network and you get paid for their web sites on the internet marketers. If you'd like to help others make money, you cannot run a lasting business and guess which one is going to help folks get ahead in their back yards. General Question: How exactly do I begin to learn everything you need to add it to learn ways to use. <br><br>95 affiliate fee goes directly to you. Not with Empower Network is, exactly? Before you even join, as long as they're customers of Solavei. I mean you are not just something that can modify their life. |
| [[Image:Soyuz rocket ASTP.jpg|thumb|upright=1.2|A [[Soyuz-U]], at [[Baikonur]]'s [[Gagarin's Start|Site 1/5]] in [[Kazakhstan]]]]
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| A '''rocket''' is a [[missile]], [[spacecraft]], [[aircraft]] or other [[vehicle]] that obtains [[thrust]] from a [[rocket engine]]. Rocket engine exhaust is formed entirely from [[propellant]]s carried within the rocket before use.<ref name="RPE7">{{harvnb|Sutton|2001}} chapter 1</ref> Rocket engines work by [[Reaction (physics)|action and reaction]]. Rocket engines push rockets forward simply by throwing their exhaust backwards extremely fast.
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| Rockets are relatively lightweight and powerful, capable of generating large accelerations and of attaining [[escape velocity|extremely high speeds]] with reasonable efficiency. Rockets are not reliant on the atmosphere and work very well in space.
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| Rockets for military and recreational uses date back to at least 13th century [[China]].<ref name="NASAEARLY">{{harvnb|MSFC History Office}} "Rockets in Ancient Times (100 B.C. to 17th Century)"</ref> Significant scientific, interplanetary and industrial use did not occur until the 20th century, when rocketry was the enabling technology for the [[Space Age]], including [[Apollo 11|setting foot on the moon]]. Rockets are now used for [[fireworks]], [[weapon]]ry, [[ejection seat]]s, [[launch vehicle]]s for [[artificial satellite]]s, [[human spaceflight]], and [[space exploration]].
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| [[Chemical rocket]]s are the most common type of high performance rocket and they typically create their exhaust by the combustion of [[rocket propellant]]. Chemical rockets store a large amount of energy in an easily released form, and can be very dangerous. However, careful design, testing, construction and use minimizes risks.
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| ==History of rockets==
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| {{Main|History of rockets}}
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| {{See also|Timeline of rocket and missile technology}}
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| [[File:11th century long serpent fire arrow rocket launcher.jpg|thumb|right|180px|A depiction of the "long serpent" rocket launcher from the 11th century book ''[[Wujing Zongyao]]''. The holes in the frame are designed to keep the fire arrows separate.]]
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| ===In antiquity===
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| {{main|Fire arrow}}
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| {{See also|List of Chinese inventions}}
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| [[Image:Chinese rocket.gif|thumb|left|upright|Early Chinese rocket.]]
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| The availability of black powder ([[gunpowder]]) to propel projectiles was a precursor to experiments as weapons such as [[bomb]]s, [[cannon]], incendiary [[fire arrow]]s and rocket-propelled fire arrows.{{#tag:ref|Rockets are used to launch people into space for months or years to visit other planets! "With its ninth century AD origins in China, the knowledge of gunpowder emerged from the search by alchemists for the secrets of life, to filter through the channels of Middle Eastern culture, and take root in Europe with consequences that form the context of the studies in this volume."<ref>{{Harvnb|Buchanan|2006|p=2}}</ref>|group=nb}}{{#tag:ref|"Without doubt it was in the previous century, around +850, that the early alchemical experiments on the constituents of gunpowder, with its self-contained oxygen, reached their climax in the appearance of the mixture itself."<ref>{{Harvnb|Needham|1986|p=7}}</ref>|group=nb}} The discovery of gunpowder was probably the product of centuries of [[Alchemy|alchemical]] experimentation in which [[Taoist]] alchemists were trying to create an elixir of immortality that would allow the person ingesting it to become physically immortal.<ref name=chase>{{Harvnb|Chase|2003|pp=31–32}}</ref> However, anyone with a wood fire might have observed the acceleration of combustion that accidentally-chosen saltpetre-containing rocks would have produced.
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| Exactly when the first [[flight]]s of rockets occurred is contested.
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| Merely lighting a centimeter-sized solid lump of gunpowder on one side can cause it to move via reaction (even without a nozzle for efficiency), so confinement in a tube and other design refinements may easily have followed for the experimentally-minded with ready access to saltpetre.
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| A problem for dating the first rocket flight is that Chinese ''fire arrows'' can be either arrows with explosives attached, or arrows propelled by gunpowder. There were reports of fire arrows and 'iron pots' that could be heard for 5 [[league (unit)|leagues]] (25 km, or 15 miles) when they exploded, causing devastation for a radius of 600 meters (2,000 feet), apparently due to shrapnel.<ref name="nasa"/> A common claim is that the first recorded use of a rocket in battle was by the Chinese in 1232 against the [[Mongol]] hordes at [[Kaifeng|Kai Feng Fu]].<ref name="Martin">This is based on an old Mandarin civil service examination question that reads "Is the defense of Kai Feng Fu against the Mongols (1232) the first recorded use of cannon?".Another question from the examinations read "Fire-arms began with the use of rockets in the dynasty of Chou (B. C. 1122-255)--in what book do we first meet with the word p'ao, now used for cannon?". {{Citation |author= [[W. A. P. Martin]] | title=The Lore of Cathay or The Intellect of China |year=1901 |location=New York |publisher=Fleming H. Revell Company | page = 25|url=http://www.archive.org/stream/loreofcathayorin00martiala#page/26/mode/2up}}</ref> However, the lowering of iron pots there may have been a way for a besieged army to blow up invaders.{{#tag:ref|（云。(Rough translation: Year 1232: Among the weaponry at the defense city [[Kaifeng]] are the "thundercrash", which are made of iron pot, filled with drugs [[black powder]], that exploded after being lighted with fire, and made a noise like thunder. They could be heard from over 100 [[li (unit)|li]], and could spread on more than a third of an [[acre]], moreover they could penetrate the armours and the iron. The [[Mongol]] soldiers employed a siege carriage cloaked with cowskin, advanced to the city below, then grubbed a niche on the city-wall, which could spare a man between. The [[Jin Dynasty (1115–1234)|Jin]] defenders atop did not know what to do, but they got an advice later. Thus, they dropped the pot with an iron string from the fortress, and the pot reached to the niche area and exploded, blowing men and carriage to pieces without trace. The defenders also have the "flying [[fire-lance]]", which they infused with [[black powder]] and ignited it. This lance flamed within a range of over ten paces on the front, and no one dared to approach it. It was said that the [[Mongol]] soldiers could only be deterred by these two devices.) <ref>History of Jin ch. 113</ref>|group=nb}} A scholarly reference occurs in the Ko Chieh Ching Yuan (The Mirror of Research), states that in 998 AD a man named [[Tang Fu]] invented a fire arrow of a new kind having an iron head.<ref name="Martin"/>
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| Less controversially, one of the earliest devices recorded that used internal-combustion rocket propulsion, was the 'ground-rat,' a type of [[firework]] recorded in 1264 as having frightened the Empress-Mother Kung Sheng at a feast held in her honor by her son the [[Emperor Lizong]].<ref>{{harvnb|Crosby|2002|pp=100–103}}</ref>
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| Subsequently, one of the earliest texts to mention the use of rockets was the ''[[Huolongjing]]'', written by the Chinese artillery officer [[Jiao Yu]] in the mid-14th century. This text also mentioned the use of the first known [[multistage rocket]], the 'fire-dragon issuing from the water' (huo long chu shui), used mostly by the Chinese navy.<ref>{{Harvnb|Needham|1986|p=510}}</ref>
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| ===Spread of rocket technology===
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| [[File:Chichibu ryusei Fes 1.jpg|thumb|upright=1.05|''[[:ja:龍勢祭り|Ryusei Festival]]'' at [[Yoshida, Saitama|Yoshida town]], [[Chichibu, Saitama|Chichibu city]], [[Saitama Prefecture|Saitama]], Japan]]
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| Rocket technology was first known to [[Europe]]ans following its use by the [[Mongol]]s [[Genghis Khan]] and [[Ögedei Khan]] when they conquered parts of Russia, Eastern, and Central Europe. The Mongolians had acquired the Chinese technology by conquest of the northern part of China and by the subsequent employment of Chinese rocketry experts as [[mercenaries]] for the Mongol military. Reports of the [[Battle of Mohi]] in the year 1241 describe the use of rocket-like weapons by the Mongols against the [[Magyars]].<ref name="nasa">{{cite web|url=http://science.ksc.nasa.gov/history/rocket-history.txt|title=A brief history of rocketry|work=NASA Spacelink |accessdate=2006-08-19}}</ref> Rocket technology also spread to [[Korea]], with the 15th century wheeled [[hwacha]] that would launch [[singijeon]] rockets.{{citation needed|date=September 2013}}
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| Additionally, the spread of rockets into Europe was also influenced by the [[Ottoman Empire|Ottomans]] at the siege of [[Constantinople]] in 1453, although it is very likely that the Ottomans themselves were influenced by the Mongol invasions of the previous few centuries. In their history of rockets published on the Internet, [[NASA]] says "Rockets appear in Arab literature in 1258 A.D., describing Mongol invaders' use of them on February 15 to capture the city of Baghdad."<ref name="nasa"/>
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| Between 1270 and 1280, Hasan al-Rammah wrote ''al-furusiyyah wa al-manasib al-harbiyya'' (''The Book of Military Horsemanship and Ingenious War Devices''), which included 107 gunpowder recipes, 22 of which are for rockets.<ref name=Gunpowder>{{harvnb|Hassan|a}}</ref> According to [[Ahmad Y Hassan]], al-Rammah's recipes were more explosive than rockets used in China at the time.<ref name=Hassan-Chemical>{{harvnb|Hassan|b}}</ref>{{Verify credibility|date=September 2010}} The terminology used by al-Rammah indicated a Chinese origin for the gunpowder weapons he wrote about, such as rockets and fire lances.<ref name="Jack Kelly 2005 22">{{cite book |url=http://books.google.com/books?id=8xfs8tC8Ow0C&pg=PA22&dq=Around+1240+the+Arabs+acquired+knowledge+of+saltpeter+(%E2%80%9CChinese+snow%E2%80%9D)+from+the+East,+perhaps+through+India.+They+knew+of+gunpowder+soon+afterward.+They+also+learned+about+fireworks+(%E2%80%9CChinese+flowers%E2%80%9D)+and+rockets+(%E2%80%9CChinese+arrows%E2%80%9D).&hl=en&ei=-63mTuyHJIX10gHyipT-CQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CDEQ6AEwAA#v=onepage&q=Around%201240%20the%20Arabs%20acquired%20knowledge%20of%20saltpeter%20(%E2%80%9CChinese%20snow%E2%80%9D)%20from%20the%20East%2C%20perhaps%20through%20India.%20They%20knew%20of%20gunpowder%20soon%20afterward.%20They%20also%20learned%20about%20fireworks%20(%E2%80%9CChinese%20flowers%E2%80%9D)%20and%20rockets%20(%E2%80%9CChinese%20arrows%E2%80%9D).&f=false|title=Gunpowder: Alchemy, Bombards, and Pyrotechnics: The History of the Explosive that Changed the World|author=Jack Kelly|accessdate=2011-11-28 |edition=illustrated |series= |volume= |date= |year=2005 |month= |publisher=Basic Books |location= |language= |isbn=0-465-03722-4 |page=22 |pages= |quote=Around 1240 the Arabs acquired knowledge of saltpeter (“Chinese snow”) from the East, perhaps through India. They knew of gunpowder soon afterward. They also learned about fireworks (“Chinese flowers”) and rockets (“Chinese arrows”). Arab warriors had acquired fire lances by 1280. Around that same year, a Syrian named Hasan al-Rammah wrote a book that, as he put it, "treat of machines of fire to be used for amusement of for useful purposes." He talked of rockets, fireworks, fire lances, and other incendiaries, using terms that suggested he derived his knowledge from Chinese sources. He gave instructions for the purification of saltpeter and the recipes for making different types of gunpowder. }}</ref> [[Ibn al-Baitar|Ibn al-Baytar]], an Arab from Spain who had immigrated to Egypt, gave the name "snow of China" ({{lang-ar|ثلج الصين}} thalj al-Sin) to describe saltpetre. Al-Baytar died in 1248.<ref>{{cite book |url=http://books.google.com/books?id=fNZBSqd2cToC&pg=PA22&dq=The+first+definite+mention+of+saltpetre+in+an+Arabic+work+is+that+in+al-Baytar+(d.+1248),+written+towards+the+end+of+his+life,+where+it+is+called+%22snow+of+China.%22+Al-Baytar+was+a+Spanish+Arab&hl=en&ei=IQbUTs7uGene0QGKkr2bBg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CDMQ6AEwAA#v=onepage&q=The%20first%20definite%20mention%20of%20saltpetre%20in%20an%20Arabic%20work%20is%20that%20in%20al-Baytar%20(d.%201248)%2C%20written%20towards%20the%20end%20of%20his%20life%2C%20where%20it%20is%20called%20%22snow%20of%20China.%22%20Al-Baytar%20was%20a%20Spanish%20Arab&f=false |title=A history of Greek fire and gunpowder |author=James Riddick Partington |accessdate=2011-11-28 |edition=reprint, illustrated |series= |volume= |date= |year=1960 |month= |publisher=JHU Press |location= |language= |isbn=0-8018-5954-9 |page=22 |pages= |quote=The first definite mention of saltpetre in an Arabic work is that in al-Baytar (d. 1248), written towards the end of his life, where it is called "snow of China." Al-Baytar was a Spanish Arab, although he travelled a good deal and lived for a time in Egypt. }}</ref><ref>{{cite book |url=http://books.google.com/books?id=X7e8rHL1lf4C&pg=PA45&dq=William+of+Rubruck+(or+Ruysbroek).+He+returned+in+1257,+and+in+the+following+year+there+are+reports+of+experiments+with+gunpowder+and+rockets+at+Cologne.+Then+a+friend+of+William+of+Rubruck,+Roger+Bacon,+gave+the+first+account+of+gunpowder+and+its+use+in+fire&hl=en&ei=yLbVTpDPOILz0gGqo_z7AQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CDMQ6AEwAA#v=onepage&q=William%20of%20Rubruck%20(or%20Ruysbroek).%20He%20returned%20in%201257%2C%20and%20in%20the%20following%20year%20there%20are%20reports%20of%20experiments%20with%20gunpowder%20and%20rockets%20at%20Cologne.%20Then%20a%20friend%20of%20William%20of%20Rubruck%2C%20Roger%20Bacon%2C%20gave%20the%20first%20account%20of%20gunpowder%20and%20its%20use%20in%20fire&f=false|title=Technology in world civilization: a thousand-year history |author=Arnold Pacey|accessdate=2011-11-28 |edition=reprint, illustrated |series= |volume= |date= |year=1991 |month= |publisher=MIT Press |location= |language= |isbn=0-262-66072-5 |page=45 |pages= |quote=Europeans were prompted by all this to take a closer interest in happenings far to the east. Four years after the invasion of 1241, the pope sent an ambassador to the Great Khan's capital in Mongolia. Other travellers followed later, of whom the most interesting was William of Rubruck (or Ruysbroek). He returned in 1257, and in the following year there are reports of experiments with gunpowder and rockets at Cologne. Then a friend of William of Rubruck, Roger Bacon, gave the first account of gunpowder and its use in fireworks to be written in Europe. A form of gunpowder had been known in China since before AD 900, and as mentioned earlier...Much of this knowledge had reached the Islamic countries by then, and the saltpetre used in making gunpowder there was sometimes referred to, significantly, as 'Chinese snow'.}}</ref> The earlier Arab historians call saltpeter "Chinese snow" and " Chinese salt;" <ref>Original from the University of Michigan{{cite book |url=http://books.google.com/books?id=ZivnAAAAMAAJ&pg=PA1033&dq=The+Arabs+learned+of+gunpowder+during+this+century+and+they+called+saltpeter+%22+Chinese+snow%22+and+the+rocket+%22Chinese&hl=en&ei=UobmTr_CIsLl0QGr1ZTzCA&sa=X&oi=book_result&ct=result&resnum=4&ved=0CEMQ6AEwAw#v=onepage&q=The%20Arabs%20learned%20of%20gunpowder%20during%20this%20century%20and%20they%20called%20saltpeter%20%22%20Chinese%20snow%22%20and%20the%20rocket%20%22Chinese&f=false|title=The people's cyclopedia of universal knowledge with numerous appendixes invaluable for reference in all departments of industrial life... |author=|accessdate=2011-11-28 |edition= |series= |volume=Volume 2 of The People's Cyclopedia of Universal Knowledge with Numerous Appendixes Invaluable for Reference in All Departments of Industrial Life |date= |year=1897 |month= |publisher=Eaton & Mains |location=NEW YORK |language= |isbn= |page=1033 |pages= |quote=Fire-arms may be defined as vessels—of whatever form— used in the propulsion of shot, shell, or bullets, to a greater or less distance, by the action of gunpowder exploded within them. The prevalent notion that gunpowder was the invention of Friar Bacon, and that cannon were first used by Edward III. of England, must be at once discarded. It is certain that gunpowder differed in no conspicuous degree from the Chreekfire of the Byzantine emperors, nor from the terrestrial thunder of China and India, where it had been known for many centuries before the chivalry of Europe began to fall beneath its leveling power. Niter is the natural and daily product of China and India; and there, accordingly, the knowledge of gunpowder seems to be coeval with that of the most distant historic events. The earlier Arab historians call saltpeter "Chinese snow" and " Chinese salt;" and the most ancient records of China itself show that fireworks were well known several hundred yrs. before the Christian era. From these and other circumstances it is indubitable that gunpowder was used by the Chinese as an explosive compound in prehistoric times; when they first discovered or applied its power as a propellant is less easily determined. Stone mortars, throwing missiles of 12 lbs. to a distance of 800 paces, are mentioned as having been employed in 767 A.D. by Thang's army; and in 1282 A.D. it is incontestable that the Chinese besieged in Cai'fong-fou used cannon against their Mongol enemies. Thus the Chinese must be allowed to have established their claim to an early practical knowledge of gunpowder and its effects. }}</ref><ref>Original from Harvard University {{cite book |url=http://books.google.com/books?id=9mgMAAAAYAAJ&pg=PA1033&dq=The+Arabs+learned+of+gunpowder+during+this+century+and+they+called+saltpeter+%22+Chinese+snow%22+and+the+rocket+%22Chinese&hl=en&ei=UobmTr_CIsLl0QGr1ZTzCA&sa=X&oi=book_result&ct=result&resnum=5&ved=0CEgQ6AEwBA#v=onepage&q=The%20Arabs%20learned%20of%20gunpowder%20during%20this%20century%20and%20they%20called%20saltpeter%20%22%20Chinese%20snow%22%20and%20the%20rocket%20%22Chinese&f=false|title=The standard American encyclopedia of arts, sciences, history, biography, geography, statistics, and general knowledge, Volume 3 |author=|editor=John Clark Ridpath|accessdate=2011-11-28 |edition= |series= |volume= |date= |year=1897 |month= |publisher=Encyclopedia publishing co. |location=156 FIFTH AVENUE, NEW YORK |language= |isbn= |page=1033 |pages= |quote=Fire-arms may be defined as vessels—of whatever form— used in the propulsion of shot, shell, or bullets, to a greater or less distance, by the action of gunpowder exploded within them. The prevalent notion that gunpowder was the invention of Friar Bacon, and that cannon were first used by Edward III. of England, must be at once discarded. It is certain that gunpowder differed in no conspicuous degree from the Greek fire of the Byzantine emperors, nor from the terrestrial thwuler of the Asian Countries , where it had been known for many centuries before the chivalry of Europe began to fall beneath its leveling power. Niter is the natural and daily product of China and India; and there, accordingly, the know ledge of gunpowder seems to be coeval with that of the most distant historic events. The earlier Arab historians call saltpeter "Chinese snow" and " Chinese salt j" and the most ancient records of China itself show that fireworks were well known several hundred yrs. before the Christian era. From these and other circumstances it is indubitable that gunpowder was used by the Chinese as an explosive compound in prehistoric times; when they first discovered or applied its power as a propellant is less easily determined. Stone mortars, throning missiles of 12 lbs. to a distance of 300 paces, are mentioned as having been employed in 757 A.D. by Thaug's army; and in 1232 A.D. it is incontestable that the Chinese besieged in Cai'fong-fou used cannon against their Mongol enemies. Thus the Chinese must be allowed to have established their claim to an early practical knowledge of gunpowder and its effects. }}</ref> The Arabs also used the name "Chinese arrows" to refer to rockets.<ref>Original from the University of Michigan{{cite book |url=http://books.google.com/books?ei=yYrmTsm5Gabk0QGUqYTJBQ&ct=result&id=fmptAAAAMAAJ&dq=The+Arabs+learned+of+saltpetre+around+the+end+of+the+thirteenth+century+when+they+were+introduced+to+it+as+%27Chinese+snow%27+and+began+to+use+rockets+which+they+called+%27Chinese+arrows%27.&q=snow+arrows|title=China considers the Middle East |author=Lillian Craig Harris|accessdate=2011-11-28 |edition=illustrated |series= |volume= |date= |year=1993 |month= |publisher=Tauris |location= |language= |isbn=1-85043-598-7 |page=25 |pages= |quote=now known precisely but, as with many other commodities, the Mongol campaigns served as one conduit. The Arabs learned of saltpetre around the end of the thirteenth century when they were introduced to it as 'Chinese snow' and began to use rockets they called 'Chinese arrows'. }}</ref><ref>Original from the University of Michigan {{cite book |url=http://books.google.com/books?ei=uYvmTpzlKqb00gH2z9DvBQ&ct=result&id=NZRFAAAAMAAJ&dq=Following+the+Mongol+conquest+of+much+of+Asia+the+Arabs+became+acquainted+with+saltpeter+sometime+before+the+end+of+the+thirteenth+century.+They+called+it+Chinese+snow%2C+as+they+called+the+rocket+the+Chinese+arrow.+Roger+Bacon+%7Bca&q=snow+arrow|title=The invention of printing in China and its spread westward |author=Thomas Francis Carter|accessdate=2011-11-28 |edition=2 |series= |volume= |date= |year=1955 |month= |publisher=Ronald Press Co. |location= |language= |isbn= |page=126 |pages= |quote=the Khitan, and again in the wars against the invading Jurchen in 1125-27 and 1161-62. Following the Mongol conquest of much of Asia the Arabs became acquainted with saltpeter sometime before the end of the thirteenth century. They called it Chinese snow, as they called the rocket the Chinese arrow. Roger Bacon (ca. 1214 to ca. 1294) is the first European writer to mention gunpowder, though whether he learned of it through his study of}}</ref><ref>Original from the University of Michigan {{cite book |url=http://books.google.com/books?ei=CInmTrfFMMna0QGr5YFz&ct=result&id=O2k5AAAAMAAJ&dq=Gunpowder+appeared+in+Europe+in+the+thirteenth+century.+The+Arabs+learned+of+gunpowder+during+this+century+and+they+called+saltpeter+%22Chinese+snow%22+and+the+rocket+%22Chinese+arrow.%22+Roger+Bacon+was+the+first+European+to+mention+gunpowder&q=snow+arrow|title=American sociological review, Volume 10 |coauthors=Frank Hamilton Hankins, American Sociological Association, American Sociological Society, JSTOR (Organization)|accessdate=2011-11-28 |edition= |series= |volume= |date= |year=1963 |month= |publisher=American Sociological Association |location= |language= |isbn= |page=598 |pages= |quote=Gunpowder appeared in Europe in the thirteenth century. The Arabs learned of gunpowder during this century and they called saltpeter "Chinese snow" and the rocket "Chinese arrow." Roger Bacon was the first European to mention gunpowder and he may have learend it from the Arabs or from his fellow Franciscan, Friar William of Rubruck. Friar William was in Mongolia in}}</ref><ref>{{cite book |url=http://books.google.com/books?ei=CInmTrfFMMna0QGr5YFz&ct=result&id=yqI1AAAAIAAJ&dq=Gunpowder+appeared+in+Europe+in+the+thirteenth+century.+The+Arabs+learned+of+gunpowder+during+this+century+and+they+called+saltpeter+%22Chinese+snow%22+and+the+rocket+%22Chinese+arrow.%22+Roger+Bacon+was+the+first+European+to+mention+gunpowder&q=snow+arrow|title=Perspectives on the social order: readings in sociology |author=|editor=Hugh Laurence Ross|accessdate=2011-11-28 |edition= |series= |volume= |date= |year=1963 |month= |publisher=McGraw-Hill |location= |language= |isbn= |page=129 |pages= |quote=Gunpowder appeared in Europe in the thirteenth century. The Arabs learned of gunpowder during this century and they called saltpeter "Chinese snow" and the rocket "Chinese arrow." Roger Bacon was the first European to mention gunpowder and he may have learend it from the Arabs or from his fellow Franciscan, Friar William of Rubruck. Friar William was in Mongolia in 1254 and Roger Bacon was personally acquainted with him after his return }}</ref><ref>Original from the University of California {{cite book |url=http://books.google.com/books?ei=PovmTrK0DuHb0QHd29jbBQ&ct=result&id=gN-6AAAAIAAJ&dq=The+Arabs+learned+of+saltpetre+around+the+end+of+the+thirteenth+century+when+they+were+introduced+to+it+as+%27Chinese+snow%27+and+began+to+use+rockets+which+they+called+%27Chinese+arrows%27.&q=snow|title=The invention of printing in China and its spread westward |author=Thomas Francis Carter|accessdate=2011-11-28 |edition= |series= |volume= |date= |year=1925 |month= |publisher=Columbia university press |location= |language= |isbn= |page=92 |pages= |quote=When the use of these grenades first began is still obscure. They were apparently used in the battles of 1161 and 1162 , and again by the northern Chinese against the Mongols in 1232. The Arabs became acquainted with saltpeter some time before the end of the thirteenth century and calledin Chinese snow, as the called the rocket the Chinese arrow. Roger Bacon (c. 1214 to c. 1294) is the first European writer to mention gunpowder, though whether he learned of it. }}</ref><ref>Original from the University of Michigan {{cite book |url=http://books.google.com/books?ei=S6zmTvmUEYLl0QGwvtzwCQ&ct=result&id=bRJmAAAAMAAJ&dq=However%2C+the+first+Arab+mention+of+saltpetre+occurs+towards+the+end+of+the+thirteenth+century%2C+when+it+is+called+%27Chinese+snow%27.+In+any+case%2C+gunpowder+became+known+in+Europe+a+short+time+after+it+was+used+in+warfare+in+China&q=However%2C+the+first+Arab+mention+of+saltpetre+occurs+towards+the+end+of+the+thirteenth+century%2C+when+it+is+called+%27Chinese+snow%27.+In+any+case%2C+gunpowder+became+known+in+Europe+a+short+time+after+it+was+used+in+warfare+in+China|title=East-West passage: the travel of ideas, arts, and inventions between Asia and the Western world, Volume 1971, Part 2 |author=Michael Edwardes|accessdate=2011-11-28 |edition=illustrated |series= |volume= |date= |year=1971 |month= |publisher=Taplinger |location= |language= |isbn= |page=82 |pages= |quote=However, the first Arab mention of saltpetre occurs towards the end of the thirteenth century, when it is called 'Chinese snow'. In any case, gunpowder became known in Europe a short time after it was used in warfare in China }}</ref><ref>Original from the University of California {{cite book |url=http://books.google.com/books?ei=UobmTr_CIsLl0QGr1ZTzCA&ct=result&id=zd66AAAAIAAJ&dq=The+Arabs+learned+of+gunpowder+during+this+century+and+they+called+saltpeter+%22+Chinese+snow%22+and+the+rocket+%22Chinese&q=snow|title=The invention of printing in China and its spread westward |author=Thomas Francis Carter|accessdate=2011-11-28 |edition=2 |year=1955 |publisher=Ronald Press Co.|page=126 |quote=Following the Mongol conquest of much of Asia the Arabs became acquainted with saltpeter sometime before the end of the thirteenth century. They called it Chinese snow, as they called the rocket the Chinese arrow.}}</ref> The Arabs attached "Chinese" to various names for gunpowder related objects. "Chinese flowers" was the name for fireworks, while "Chinese Snow" was given to saltpeter and "Chinese arrows" to rockets.<ref name="Jack Kelly 2005 22"/> While saltpeter was called "Chinese Snow" by Arabs, it was called "Chinese salt" by the Iranians/Persians.<ref>{{cite book |url=http://books.google.com/books?id=CVNoJydnGAoC&pg=PA304&dq=The+Arabic+term+for+saltpetre+is+'Chinese+snow'+while+the+Persian+usage+is+'Chinese+salt'.28&hl=en&ei=b6vmToLRM8jd0QHeyeTlCQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CDAQ6AEwAA#v=onepage&q=The%20Arabic%20term%20for%20saltpetre%20is%20'Chinese%20snow'%20while%20the%20Persian%20usage%20is%20'Chinese%20salt'.28&f=false|title=Ideas: A History of Thought and Invention, from Fire to Freud |author=Peter Watson|accessdate=2011-11-28 |edition=illustrated, annotated |series= |volume= |date= |year=2006 |month= |publisher=HarperCollins |location= |language= |isbn=0-06-093564-2 |page=304 |pages= |quote=The first use of a metal tube in this context was made around 1280 in the wars between the Song and the Mongols, where a new term, chong, was invented to describe the new horror...Like paper, it reached the West via the Muslims, in this case the writings of the Andalusian botanist Ibn al-Baytar, who died in Damascus in 1248. The Arabic term for saltpetre is 'Chinese snow' while the Persian usage is 'Chinese salt'.28 }}</ref><ref>{{cite book |url=http://books.google.com/books?id=1h9zzSH-NmwC&pg=PA365&dq=In+either+case,+there+is+linguistic+evidence+of+Chinese+origins+of+the+technology:+in+Damascus,+Arabs+called+the+saltpeter+used+in+making+gunpowder+%22+Chinese+snow,%22+while+in+Iran+it+was+called+%22Chinese+salt.%22+Whatever+the+migratory+route&hl=en&ei=ia3mTuHsD8HL0QHepZHtCQ&sa=X&oi=book_result&ct=result&resnum=1&ved=0CDAQ6AEwAA#v=onepage&q=In%20either%20case%2C%20there%20is%20linguistic%20evidence%20of%20Chinese%20origins%20of%20the%20technology%3A%20in%20Damascus%2C%20Arabs%20called%20the%20saltpeter%20used%20in%20making%20gunpowder%20%22%20Chinese%20snow%2C%22%20while%20in%20Iran%20it%20was%20called%20%22Chinese%20salt.%22%20Whatever%20the%20migratory%20route&f=false|title=The age of wars of religion, 1000-1650: an encyclopedia of global warfare and civilization |author=Cathal J. Nolan|accessdate=2011-11-28 |edition=illustrated |series= |volume=Volume 1 of Greenwood encyclopedias of modern world wars |date= |year=2006 |month= |publisher=Greenwood Publishing Group |location= |language= |isbn=0-313-33733-0 |page=365 |pages= |quote=In either case, there is linguistic evidence of Chinese origins of the technology: in Damascus, Arabs called the saltpeter used in making gunpowder " Chinese snow," while in Iran it was called "Chinese salt." Whatever the migratory route }}</ref><ref>Original from the University of Michigan {{cite book |url=http://books.google.com/books?ei=RonmTrvUGsbz0gH_xuH9BQ&ct=result&id=uY_fAAAAMAAJ&dq=The+Chinese+were+certainly+acquainted+with+saltpetre%2C+the+essential+ingredient+of+gunpowder.+They+called+it+Chinese+Snow+and+employed+it+early+in+the+Christian+era+in+the+manufacture+of+fireworks+and+rockets.&q=snow|title=Artillery: its origin, heyday, and decline |author=Oliver Frederick Gillilan Hogg|accessdate=2011-11-28 |edition=illustrated |series= |volume= |date= |year=1970 |month= |publisher=Archon Books |location= |language= |isbn= |page=123 |pages= |quote=The Chinese were certainly acquainted with saltpetre, the essential ingredient of gunpowder. They called it Chinese Snow and employed it early in the Christian era in the manufacture of fireworks and rockets. }}</ref><ref>Original from the University of Michigan {{cite book |url=http://books.google.com/books?ei=qInmTpz6KePy0gGig7DmBQ&ct=result&id=aG0gAAAAMAAJ&dq=The+Chinese+were+certainly+acquainted+with+saltpetre%2C+the+essential+ingredient+of+gunpowder.+They+called+it+Chinese+Snow+and+employed+it+early+in+the+Christian+era+in+the+manufacture+of+fireworks+and+rockets.&q=snow|title=English artillery, 1326-1716: being the history of artillery in this country prior to the formation of the Royal Regiment of Artillery |author=Oliver Frederick Gillilan Hogg|accessdate=2011-11-28 |edition= |series= |volume= |date= |year=1963 |month= |publisher=Royal Artillery Institution |location= |language= |isbn= |page=42 |pages= |quote=The Chinese were certainly acquainted with saltpetre, the essential ingredient of gunpowder. They called it Chinese Snow and employed it early in the Christian era in the manufacture of fireworks and rockets. }}</ref><ref>{{cite book |url=http://books.google.com/books?ei=EormTvOcPOTX0QGTreTjBQ&ct=result&id=6DfRYDE0ViwC&dq=The+Chinese+were+certainly+acquainted+with+saltpetre%2C+the+essential+ingredient+of+gunpowder.+They+called+it+Chinese+snow+and+used+it+early+in+the+Christian+era+in+the+manufacture+of+fireworks+and+rockets.&q=snow|title=Clubs to cannon: warfare and weapons before the introduction of gunpowder |author=Oliver Frederick Gillilan Hogg|accessdate=2011-11-28 |edition=reprint |series= |volume= |date= |year=1993 |month= |publisher=Barnes & Noble Books |location= |language= |isbn=1-56619-364-8 |page=216 |pages= |quote=The Chinese were certainly acquainted with saltpetre, the essential ingredient of gunpowder. They called it Chinese snow and used it early in the Christian era in the manufacture of fireworks and rockets. }}</ref>
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| The name ''Rocket'' comes from the [[Italian language|Italian]] ''Rocchetta'' (i.e. ''little fuse''), a name of a small firecracker created by the Italian artificer Muratori in 1379.<ref name="vonbraunrocketry">{{harvnb|von Braun|Ordway|1966}}{{Page needed|date=September 2010}}</ref>
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| [[Image:Conrad Kyeser's Bellifortis c 1405 fig 1.jpg|thumb|left|upright|Kyeser was infatuated with the [[Alexander romance|legend of Alexander the Great]]: here Alexander holds a rocket, the first depiction of one]]
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| [[Konrad Kyeser]] described rockets in his famous military treatise [[Bellifortis]] around 1405.<ref>"Rockets and Missiles: The Life Story of a Technology", A. Bowdoin Van Riper,p.10</ref>
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| Between 1529 and 1556 [[Conrad Haas]] wrote a book that described rocket technology that combined [[fireworks]] and weapons technologies. This manuscript was discovered in 1961, in the Sibiu public records (Sibiu public records ''Varia II 374''). His work dealt with the theory of motion of multi-stage rockets, different fuel mixtures using [[liquid fuel]], and introduced [[delta (letter)|delta]]-shape [[fin]]s and bell-shaped [[nozzle]]s.<ref>{{cite web|url=http://www.sibiweb.de/vip/haas/ |title=CONRAD HAAS Raketenpionier in Siebenbürgen (german) |publisher=Sibiweb.de |date= |accessdate=2012-12-10}}</ref>
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| ''Lagari Hasan Çelebi'' was a [[legend]]ary [[Ottoman Empire|Ottoman]] aviator who, according to an account written by [[Evliya Çelebi]], made a successful manned rocket [[flight]]. Evliya Çelebi purported that in 1633 [[Lagari Hasan Çelebi]] launched in a 7-winged rocket using 50 okka (140 lbs) of [[gunpowder]] from [[Sarayburnu]], the point below [[Topkapı Palace]] in [[Istanbul]].
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| [[Image:Lagari.jpg|thumb|left|upright|[[Lagâri Hasan Çelebi]]'s rocket flight depicted in a 17th-century engraving]]
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| For over two centuries, the work of [[Polish-Lithuanian Commonwealth]] [[szlachta|nobleman]] [[Kazimierz Siemienowicz]] "''Artis Magnae Artilleriae pars prima''" ("Great Art of Artillery, the First Part", also known as "The Complete Art of Artillery"), was used in [[Europe]] as a basic artillery manual.<ref name="Nowak182">{{harvnb|Nowak|1969|p=182}}</ref> First printed in [[Amsterdam]] in 1650 it was translated to [[French language|French]] in 1651, [[German language|German]] in 1676, [[English language|English]] and [[Dutch language|Dutch]] in 1729 and [[Polish language|Polish]] in 1963. The book provided the standard designs for creating rockets, [[Incendiary device|fireballs]], and other [[pyrotechnic]] devices. It contained a large chapter on caliber, construction, production and properties of rockets (for both military and civil purposes), including [[Multistage rocket|multi-stage]] rockets, batteries of rockets, and rockets with [[delta wing]] [[stabilizer (aircraft)|stabilizer]]s (instead of the common guiding rods ("bottle rockets"), which are also aerodynamic stabilizers but less efficient than fins).
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| ===Metal-cylinder rocket artillery===
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| In 1792, the first [[Mysorean Rockets|iron-cased rockets]] were successfully developed and used by [[Hyder Ali]] and his son [[Tipu Sultan]], rulers of the [[Kingdom of Mysore]] in [[India]] against the larger [[British East India Company]] forces during the [[Anglo-Mysore Wars]]. The British then took an active interest in the technology and developed it further during the 19th century. The Mysore rockets of this period were much more advanced than the British had previously seen, chiefly because of the use of iron tubes for holding the propellant; this enabled higher thrust and longer range for the missile (up to 2 km range). After Tipu's eventual defeat in the [[Fourth Anglo-Mysore War]] and the capture of the Mysore iron rockets, they were influential in British rocket development, inspiring the [[Congreve rocket]], which was soon put into use in the [[Napoleonic Wars]].<ref>Roddam Narasimha (1985). [http://www.nal.res.in/pdf/pdfrocket.pdf Rockets in Mysore and Britain, 1750-1850 A.D.] National Aeronautical Laboratory and Indian Institute of Science.</ref>
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| ===Accuracy of early rockets===
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| [[Image:Congreve rockets.gif|thumb|The [[Congreve rocket]] ]]
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| [[William Congreve (inventor)|William Congreve]], son of the Comptroller of the Royal Arsenal, Woolwich, London, became a major figure in the field. From 1801, Congreve researched on the original design of [[Mysorean Rockets|Mysore rockets]] and set on a vigorous development program at the Arsenal's laboratory.<ref name="congreve">{{harvnb|Stephens|1887}}</ref> Congreve prepared a new propellant mixture, and developed a rocket motor with a strong iron tube with conical nose. This early [[Congreve rocket]] weighed about 32 pounds (14.5 kilograms). The Royal Arsenal's first demonstration of solid fuel rockets was in 1805. The rockets were effectively used during the Napoleonic Wars and the War of 1812. Congreve published three books on rocketry.<ref>{{harvnb|Van Riper|2004}}{{Page needed|date=September 2010}}</ref>
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| From there, the use of military rockets spread throughout the western world. At the [[Battle of Baltimore]] in 1814, the rockets fired on [[Fort McHenry]] by the [[rocket vessel]] [[HMS Erebus (1807)|HMS ''Erebus'']] were the source of the ''rockets' red glare'' described by [[Francis Scott Key]] in [[The Star-Spangled Banner]].<ref>[http://www.nps.gov/history/history/online_books/hh/5/hh5l.htm British Rockets] at the US National Parks Service, Fort McHenry National Monument and Historic Shrine. Retrieved February 2008.</ref> Rockets were also used in the [[Battle of Waterloo]].<ref>[http://www.napoleonic-literature.com/Articles/Rockets/History_of_Rockets.htm History of the Rocket - 1804 to 1815] by [[Gareth Glover]]</ref>
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| Early rockets were very inaccurate. Without the use of spinning or any [[gimbal]]ling of the thrust, they had a strong tendency to veer sharply off of their intended course. The early [[Mysorean rockets]] and their successor British [[Congreve rocket]]s<ref name="congreve"/> reduced this somewhat by attaching a long stick to the end of a rocket (similar to modern bottle rockets) to make it harder for the rocket to change course. The largest of the Congreve rockets was the 32-pound (14.5 kg) Carcass, which had a 15-foot (4.6 m) stick. Originally, sticks were mounted on the side, but this was later changed to mounting in the center of the rocket, reducing drag and enabling the rocket to be more accurately fired from a segment of pipe.
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| The accuracy problem was greatly improved in 1844 when [[William Hale (British inventor)|William Hale]]<ref name="SMITH">{{harvnb|Space History Division|1999}}</ref> modified the rocket design so that thrust was slightly [[thrust vectoring|vectored]], causing the rocket to spin along its axis of travel like a bullet. The Hale rocket removed the need for a rocket stick, travelled further due to reduced air resistance, and was far more accurate.
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| In 1865 the British Colonel [[Edward Mounier Boxer]] built an improved versione of the Congreve rocket placing two rockets in one tube, one behind the other.<ref>[http://freespace.virgin.net/iw.history/rockets/dennett.htm History of Rockets-John Dennett, Isle of Wight Rocket man]</ref>
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| ===Theories of interplanetary rocketry===
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| [[Image:Tsiolkovsky.jpg|thumb|left|upright|[[Konstantin Tsiolkovsky]] published the first work on space travel, which was inspired by the writings of Jules Verne]]
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| At the beginning of the 20th Century, there was a burst of scientific investigation into interplanetary travel, largely driven by the inspiration of fiction by writers such as [[Jules Verne]] and [[H.G.Wells]]. Scientists seized on the rocket as a technology that was able to achieve this in real life.
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| In 1903, high school mathematics teacher [[Konstantin Tsiolkovsky]] (1857–1935), published ''Исследование мировых пространств реактивными приборами''<ref>[http://epizodsspace.testpilot.ru/bibl/dorev-knigi/ciolkovskiy/issl-03st.html Tsiolkovsky's Исследование мировых пространств реактивными приборами - ''The Exploration of Cosmic Space by Means of Reaction Devices'' (Russian paper)]</ref> (''The Exploration of Cosmic Space by Means of Reaction Devices''), the first serious scientific work on space travel. The [[Tsiolkovsky rocket equation]]—the principle that governs rocket propulsion—is named in his honor (although it had been discovered previously).<ref>{{harvnb|Johnson|1995|pp=499–521}}</ref> He also advocated the use of liquid hydrogen and oxygen for propellant, calculating their maximum exhaust velocity. His work was essentially unknown outside the Soviet Union, but inside the country it inspired further research, experimentation and the formation of the [[Society for Studies of Interplanetary Travel]] in 1924.
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| In 1912, [[Robert Esnault-Pelterie]] published a lecture<ref>{{harvnb|Esnault-Pelterie|1913}}</ref> on rocket theory and interplanetary travel. He independently derived Tsiolkovsky's rocket equation, did basic calculations about the energy required to make round trips to the Moon and planets, and he proposed the use of atomic power (i.e. Radium) to power a jet drive.
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| [[Image:Dr. Robert H. Goddard - GPN-2002-000131.jpg|thumb|upright|[[Robert H. Goddard|Robert Goddard]]]]
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| In 1912 [[Robert Goddard (scientist)|Robert Goddard]], inspired from an early age by H.G.Wells, began a serious analysis of rockets, concluding that conventional solid-fuel rockets needed to be improved in three ways.
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| First, fuel should be burned in a small combustion chamber, instead of building the entire propellant container to withstand the high pressures. Second, rockets could be arranged in stages. Finally, the exhaust speed (and thus the efficiency) could be greatly increased to beyond the speed of sound by using a [[De Laval nozzle]]. He patented these concepts in 1914.<ref>{{cite web|url=http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=1,102,653.PN.&OS=PN/1,102,653&RS=PN/1,102,653 |title=US patent 1,102,653 |publisher=Patft.uspto.gov |date=1914-07-07 |accessdate=2012-12-10}}</ref> He also independently developed the mathematics of rocket flight.
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| In 1920, Goddard published these ideas and experimental results in ''[[A Method of Reaching Extreme Altitudes]]''.<ref>{{harvnb|Goddard|1919}}</ref> The work included remarks about sending a solid-fuel rocket to the Moon, which attracted worldwide attention and was both praised and ridiculed. A New York Times editorial suggested:
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| {{cquote|That Professor Goddard, with his 'chair' in Clark College and the countenancing of the Smithsonian Institution, does not know the relation of action to reaction, and of the need to have something better than a vacuum against which to react -- to say that would be absurd. Of course he only seems to lack the knowledge ladled out daily in high schools.|||New York Times, 13 January 1920<ref>{{Cite news|first= |last= |authorlink= |coauthors= |title=Topics of the Times |url=http://it.is.rice.edu/~rickr/goddard.editorial.html |archiveurl=http://web.archive.org/web/20080209230323/http://it.is.rice.edu/~rickr/goddard.editorial.html |archivedate=2008-02-09 |publisher=New York Times |date=January 13, 1920 |accessdate=2007-06-21 }}</ref>}}
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| In 1923, [[Hermann Oberth]] (1894–1989) published ''Die Rakete zu den Planetenräumen'' ("The Rocket into Planetary Space"), a version of his doctoral thesis, after the University of Munich rejected it.<ref name="ianzer">Jürgen Heinz Ianzer, [http://www.aspera.ro/dl/oberth.pdf ''Hermann Oberth, pǎrintele zborului cosmic''] ("Hermann Oberth, Father of Cosmic Flight") (in Romanian), pp. 3, 11, 13, 15.</ref>
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| In 1924, Tsiolkovsky also wrote about [[multi-stage rocket]]s, in 'Cosmic Rocket Trains'<ref>{{cite web|author=inventors |url=http://inventors.about.com/library/inventors/blrocketTsiolkovsky.htm |title=Konstantin Tsiolkovsky - Rockets from Russia |publisher=Inventors.about.com |date=2012-04-09 |accessdate=2012-12-10}}</ref>
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| ===Modern rocketry===
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| ====Pre-World War II====
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| [[Image:Goddard and Rocket.jpg|thumb|upright|Robert Goddard and the first liquid-fueled rocket.]]
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| Modern rockets were born when Goddard attached a supersonic ([[de Laval nozzle|de Laval]]) nozzle to a liquid-fueled rocket engine's combustion chamber. These nozzles turn the hot gas from the combustion chamber into a cooler, [[hypersonic]], highly directed jet of gas, more than doubling the thrust and raising the engine efficiency from 2% to 64%.<ref>{{harvnb|Goddard|2002|pp=2,15}}</ref><ref>{{harvnb|Clary|2003|pp=44–45}}</ref> In 1926, Robert Goddard launched the world's first liquid-fueled rocket in [[Auburn, Massachusetts|Auburn]], Massachusetts.
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| During the 1920s, a number of rocket research organizations appeared worldwide. In 1927 the German car manufacturer [[Opel]] began to research rocket vehicles together with Mark Valier and the solid-fuel rocket builder Friedrich Wilhelm Sander.<ref>{{cite web|url=http://www.daviddarling.info/encyclopedia/O/Opel-RAK.html |title=The Internet Encyclopedia of Science, history of rocketry: Opel-RAK |publisher=Daviddarling.info |date= |accessdate=2012-12-10}}</ref> In 1928, Fritz von Opel drove with a rocket car, the [[Opel-RAK]].1 on the Opel raceway in Rüsselsheim, Germany. In 1928 the [[Lippisch Ente]] flew, rocket power was used to launch the manned glider, although it was destroyed on its second flight. In 1929 von Opel started at the Frankfurt-Rebstock airport with the [[Opel RAK.1|Opel-Sander RAK 1-airplane]], which was damaged beyond repair during a hard landing after its first flight.
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| In the mid-1920s, [[Weimar Republic|German]] scientists had begun experimenting with rockets that used liquid propellants capable of reaching relatively high altitudes and distances. In 1927 and also in Germany, a team of amateur rocket engineers had formed the ''[[Verein für Raumschiffahrt]]'' (German Rocket Society, or VfR), and in 1931 launched a liquid propellant rocket (using [[oxygen]] and [[petrol|gasoline]]).<ref>{{cite web|url=http://www.daviddarling.info/encyclopedia/V/Verein_fur_Raumschiffahrt.html |title=History of Rocketry: Verein für Raumschiffahrt (VfR) |publisher=Daviddarling.info |date=2007-02-01 |accessdate=2012-12-10}}</ref>
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| From 1931 to 1937 in Russia, extensive scientific work on rocket engine design occurred in [[Leningrad]] at the Gas Dynamics Laboratory there. Well-funded and staffed, over 100 experimental engines were built under the direction of [[Valentin Glushko]]. The work included [[regenerative cooling (rocket)|regenerative cooling]], [[hypergolic propellant]] ignition, and [[fuel injector]] designs that included swirling and bi-propellant mixing injectors. However, the work was curtailed by Glushko's arrest during [[Great Purge|Stalinist purges]] in 1938. Similar work was also done by the Austrian professor [[Eugen Sänger]] who worked on rocket-powered [[spaceplanes]] such as [[Silbervogel]] (sometimes called the 'antipodal' bomber.)<ref>{{cite web|url=http://www.astronautix.com/data/saenger.pdf |title=A Rocket Drive For Long Range Bombers by E. Saenger and J. Bredt, August 1944 |format=PDF |date= |accessdate=2012-12-10}}</ref>
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| On November 12, 1932 at a farm in Stockton NJ, the American Interplanetary Society's attempt to static fire their first rocket (based on German Rocket Society designs) failed in a fire.<ref>{{Citation | last1 = Winter| first1 = Frank H | last = van der Linden| first2 = Robert | title = Out of the Past | magazine = Aerospace America |date = November 2007|pages=p39}}</ref>
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| In 1930s, the ''[[Reichswehr]]'' (which in 1935 became the ''[[Wehrmacht]]'') began to take an interest in rocketry.<ref>{{harvnb|Zaloga|2003|p=3}}</ref> Artillery restrictions imposed by the [[Treaty of Versailles]] limited Germany's access to long distance weaponry. Seeing the possibility of using rockets as long-range [[artillery]] fire, the Wehrmacht initially funded the VfR team, but because their focus was strictly scientific, created its own research team. At the behest of military leaders, [[Wernher von Braun]], at the time a young aspiring [[rocket scientist]], joined the military (followed by two former VfR members) and developed long-range weapons for use in [[World War II]] by [[Nazi Germany]].<ref>{{cite web|url=http://www.russianspaceweb.com/a4.html |title=The V-2 ballistic missile |publisher=Russianspaceweb.com |date= |accessdate=2012-12-10}}</ref>
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| ====World War II====
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| [[Image:V-2 Rocket On Meillerwagen.jpg|left|thumb|A German V-2 rocket on a [[Meillerwagen]]]]
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| [[Image:V-2 rocket diagram (with English labels).svg|thumb|upright|Layout of a [[V-2 rocket]]]]
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| In 1943, production of the [[V-2 rocket]] began in Germany. It had an operational range of {{convert|300|km|mi|abbr=on}} and carried a {{convert|1000|kg|lb|abbr=on}} warhead, with an [[amatol]] explosive charge. It normally achieved an operational maximum altitude of around {{convert|90|km|mi|abbr=on}}, but could achieve {{convert|206|km|mi|abbr=on}} if launched vertically. The vehicle was similar to most modern rockets, with [[turbopump]]s, [[guidance system|inertial guidance]] and many other features. Thousands were fired at various [[Allies of World War II|Allied]] nations, mainly Belgium, as well as England and France. While they could not be intercepted, their guidance system design and single conventional warhead meant that it was insufficiently accurate against military targets. A total of 2,754 people in England were killed, and 6,523 were wounded before the launch campaign was ended. There were also 20,000 deaths of slave labour during the construction of V-2s. While it did not significantly affect the course of the war, the V-2 provided a lethal demonstration of the potential for guided rockets as weapons.<ref name=Hunt>{{harvnb|Hunt|1991|pp=72–74}}</ref><ref name=Beon>{{harvnb|Béon|1997}}{{Page needed|date=September 2010}}</ref>
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| In parallel with the guided missile programme in [[Nazi Germany]], rockets were also used on aircraft, either for assisting horizontal take-off ([[JATO]]), vertical take-off ([[Bachem Ba 349]] "Natter") or for powering them ([[Me 163]],<ref name="ww2-planes">[http://www.world-war-2-planes.com/Messerschmitt-Me-163-Komet.html "Messerschmitt Me 163 Komet."] ''World War 2 Planes''. Retrieved: 22 March 2009.</ref> etc.). During the war Germany also developed several guided and unguided air-to-air, ground-to-air and ground-to-ground missiles (see [[list of World War II guided missiles of Germany]]).
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| The Allies rocket programs were much less sophisticated, relying mostly on unguided missiles like the Soviet [[Katyusha rocket launcher|Katyusha rocket]].
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| ====Post World War II====
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| [[Image:Dornberger-Axter-von Braun.jpg|thumb|upright|[[Walter Dornberger|Dornberger]] and [[Wernher von Braun|Von Braun]] after being captured by the Allies]]
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| [[Image:Semyorka Rocket R7 by Sergei Korolyov in VDNH Ostankino RAF0540.jpg|left|thumb|upright|R-7 8K72 "[[Vostok rocket|Vostok]]" permanently displayed at the Moscow Trade Fair at [[Ostankino District|Ostankino]]; the rocket is held in place by its railway carrier, which is mounted on four diagonal beams that constitute the display pedestal. Here the railway carrier has tilted the rocket upright as it would do so into its launch pad structure -- which is missing for this display.]]
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| At the end of World War II, competing Russian, British, and US military and scientific crews raced to capture technology and trained personnel from the German rocket program at [[Peenemünde]]. Russia and Britain had some success, but the United States benefited the most. The US captured a large number of German rocket scientists, including von Braun, and brought them to the United States as part of [[Operation Overcast]].<ref>{{cite web|url=http://www.archives.gov/iwg/declassified-records/rg-330-defense-secretary/ |title=Joint Intelligence Objectives Agency. US National Archives and Records Administration |publisher=Archives.gov |date=2011-10-19 |accessdate=2012-12-10}}</ref> In America, the same rockets that were designed to rain down on [[United Kingdom|Britain]] were used instead by scientists as research vehicles for developing the new technology further. The V-2 evolved into the American [[Redstone rocket]], used in the early space program.<ref>{{harvnb|von Braun|1963|pp=452–465}}</ref>
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| After the war, rockets were used to study high-altitude conditions, by radio [[telemetry]] of temperature and pressure of the atmosphere, detection of [[cosmic rays]], and further research; notably for the [[Bell X-1]] to break the sound barrier. This continued in the US under von Braun and the others, who were destined to become part of the US scientific community.
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| Independently, in the [[Soviet space program|Soviet Union's space program]] research continued under the leadership of the chief designer [[Sergei Korolev]].<ref>{{cite web|url=http://www.nmspacemuseum.org/halloffame/detail.php?id=15 |title=International Space Hall of Fame: Sergei Korolev |publisher=Nmspacemuseum.org |date= |accessdate=2012-12-10}}</ref> With the help of German technicians, the V-2 was duplicated and improved as the [[R-1 (rocket)|R-1]], [[R-2 rocket|R-2]] and [[R-5 (rocket)|R-5]] missiles. German designs were abandoned in the late 1940s, and the foreign workers were sent home. A new series of engines built by Glushko and based on inventions of [[Aleksei Mihailovich Isaev]] formed the basis of the first ICBM, the [[R-7 (rocket)|R-7]].<ref>
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| {{cite web| url = http://www.energia.ru/english/energia/launchers/rocket-r7.html | title = Rocket R-7 | publisher = S.P.Korolev RSC Energia}}</ref> The R-7 launched the first satellite- [[Sputnik 1]], and later [[Yuri Gagarin]]-the first man into space, and the first lunar and planetary probes. This rocket is still in use today. These prestigious events attracted the attention of top politicians, along with additional funds for further research.
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| One problem that had not been solved was [[atmospheric reentry]]. It had been shown that an orbital vehicle easily had enough kinetic energy to vaporize itself, and yet it was known that meteorites can make it down to the ground. The mystery was solved in the US in 1951 when [[H. Julian Allen]] and [[Alfred J. Eggers|A. J. Eggers, Jr.]] of the [[National Advisory Committee for Aeronautics]] (NACA) made the counterintuitive discovery<ref>{{harvnb|Hansen|1987}} [http://history.nasa.gov/SP-4305/ch12.htm Chapter 12.]</ref> that a blunt shape (high drag) permitted the most effective heat shield. With this type of shape, around 99% of the energy goes into the air rather than vehicle, and this permitted safe recovery of orbital vehicles.
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| The Allen and Eggers discovery, though initially treated as a military secret, was eventually published in 1958.<ref>{{harvnb|Allen|Eggers|1958}}</ref> The Blunt Body Theory made possible the heat shield designs that were embodied in the [[Mercury program|Mercury]] and all other space capsules and space planes, enabling astronauts to survive the fiery re-entry into Earth's atmosphere.
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| [[Image:Mk 2.jpg|thumb |left|upright|Prototype of the Mk-2 Reentry Vehicle (RV), based on [[Atmospheric reentry#Blunt body entry vehicles|blunt body theory]] ]]
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| ====Cold War====
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| Rockets became extremely important militarily as modern [[intercontinental ballistic missiles]] (ICBMs) when it was realized that [[nuclear weapons]] carried on a rocket vehicle were essentially impossible for existing defense systems to stop once launched, and ICBM/Launch vehicles such as the R-7, [[Atlas (rocket family)|Atlas]] and [[Titan (rocket family)|Titan]] became the delivery platform of choice for these weapons.
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| [[File:VonBraunTeam1961.jpg|thumb|Von Braun's rocket team in 1961]]
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| Fueled partly by the [[Cold War]], the 1960s became the decade of rapid development of rocket technology particularly in the Soviet Union ([[Vostok rocket|Vostok]], [[Soyuz (rocket family)|Soyuz]], [[Proton rocket|Proton]]) and in the United States (e.g. the [[X-15]]<ref>{{cite web|url=http://history.nasa.gov/monograph18.pdf |title=(PDF) ''Hypersonics Before the Shuttle: A Concise History of the X-15 Research Airplane'' (NASA SP-2000-4518, 2000) |format=PDF |date= |accessdate=2012-12-10}}</ref> and [[X-20 Dyna-Soar]]<ref>{{harvnb|Houchin|2006}}{{Page needed|date=September 2010}}</ref> aircraft). There was also significant research in other countries, such as Britain, Japan, Australia, etc., and a growing use of rockets for [[Space exploration]], with pictures returned from the far side of the [[Moon]] and unmanned flights for [[Mars exploration]].
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| In America the manned programmes, [[Project Mercury]], [[Project Gemini]] and later the [[Apollo programme]] culminated in 1969 with the first manned [[moon landing|landing on the moon]] via the [[Saturn V]], causing the New York Times to retract their earlier editorial implying that spaceflight couldn't work:
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| {{Cquote|Further investigation and experimentation have confirmed the findings of Isaac Newton in the 17th century and it is now definitely established that a rocket can function in a vacuum as well as in an atmosphere. The Times regrets the error.|||New York Times, 17 June 1969 - A Correction<ref>{{cite web|last=Kuntz |first=Tom |url=http://www.nytimes.com/2001/11/14/news/150th-anniversary-1851-2001-the-facts-that-got-away.html |title=New York Times 17 June 1969 - A Correction |publisher=Nytimes.com |date=2001-11-14 |accessdate=2012-12-10}}</ref>}}
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| In the 1970s America made further lunar landings, before cancelling the Apollo programme in 1975. The replacement vehicle, the partially reusable '[[Space Shuttle]]' was intended to be cheaper,<ref>{{harvnb|GAO|1972}}{{Page needed|date=September 2010}}</ref> but this large reduction in costs was largely not achieved. Meanwhile in 1973, the expendable [[Ariane (rocket)|Ariane]] programme was begun, a launcher that by the year 2000 would capture much of the [[Geosynchronous satellite|geosat]] market.
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| ====Current day====
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| [[Image:SpaceShipOne Nose.jpg|thumb|upright|SpaceShipOne]]
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| Rockets remain a popular military weapon. The use of large battlefield rockets of the V-2 type has given way to guided [[missiles]]. However rockets are often used by [[helicopter]]s and light aircraft for ground attack, being more powerful than [[machine gun]]s, but without the recoil of a heavy [[cannon]] and by the early 1960s [[air-to-air missile]]s became favored. Shoulder-launched rocket weapons are widespread in the anti-tank role due to their simplicity, low cost, light weight, accuracy and high level of damage. Current artillery systems such as the [[MLRS]] or [[BM-30 Smerch]] launch multiple rockets to saturate battlefield targets with munitions.{{Citation needed|date=June 2009}}
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| Commercially, rocketry is the enabler of all [[space technology|space technologies]] particularly [[satellite]]s, many of which impact people's everyday lives in almost countless ways.<ref>{{cite web|url=http://www.losangeles.af.mil/library/factsheets/factsheet.asp?id=5311 |title=Global Positioning Systems Wing |publisher=Losangeles.af.mil |date=2012-11-21 |accessdate=2012-12-10}}</ref>
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| Scientifically, rocketry has opened a window on the universe, allowing the launch of [[space probe]]s to explore the [[solar system]] and space-based [[telescopes]] to obtain a clearer view of the rest of the [[universe]].<ref>{{cite web|url=http://www.nasa.gov/audience/forstudents/postsecondary/features/F_NASA_Great_Observatories_PS.html |title=NASA's great observatories |publisher=Nasa.gov |date= |accessdate=2012-12-10}}</ref>
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| However, it is probably [[manned spaceflight]] that has predominantly caught the imagination of the public. Vehicles such as the [[Space Shuttle]] for scientific research, the [[Soyuz spacecraft|Soyuz]] increasingly for orbital tourism and [[SpaceShipOne]] for suborbital tourism may show a trend towards greater commercialisation of manned rocketry.<ref>{{cite web|url=http://www.futron.com/pdf/resource_center/white_papers/SpaceTourismMarketStudy.pdf |title=Futron report |publisher=Futron.com |date= |accessdate=2012-12-10}}</ref>
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| ==Types==
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| ;Vehicle configurations
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| [[File:Ap4-s67-50531.jpg|thumb|right||thumb|upright|[[Saturn V]] is the biggest rocket to have successfully flown.]]
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| [[File:Apollo 15 launch.ogg|thumb|upright|Launch of ''[[Apollo 15]]'' [[Saturn V]] rocket: ''T'' − 30 s through ''T'' + 40 s]]
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| Rocket vehicles are often constructed in the archetypal tall thin "rocket" shape that takes off vertically, but there are actually many different types of rockets including:<ref>{{cite web|url=http://www.hq.nasa.gov/pao/History/conghand/vehicles.htm |title=NASA History: Rocket vehicles |publisher=Hq.nasa.gov |date= |accessdate=2012-12-10}}</ref><ref>{{cite web|url=http://strangevehicles.greyfalcon.us/OPEL%20ROCKET%20VEHICLES.htm |title=OPEL Rocket vehicles |publisher=Strangevehicles.greyfalcon.us |date= |accessdate=2012-12-10}}</ref>
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| *tiny models such as [[balloon rocket]]s, [[water rocket]]s, [[skyrocket]]s or [[model rocket|small solid rockets]] that can be purchased at a [[hobby store]]
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| *[[missile]]s
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| *[[launch vehicle|space rocket]]s such as the enormous [[Saturn V]] used for the [[Apollo program]]
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| *[[rocket car]]s
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| *rocket bike
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| *[[rocket-powered aircraft]] (including rocket assisted takeoff of conventional aircraft- [[JATO]])
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| *[[rocket sled]]s
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| *[[Opel-RAK|rocket train]]s
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| *[[VA-111 Shkval|rocket torpedo]]s<ref>{{harvnb|Polmar|2004|p=304}}</ref><ref>{{harvnb|Baker|2000|p=581}}</ref>
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| *rocket-powered [[jet pack]]s<ref>{{cite web|url=http://www.rocketman.org |title=The Rocketman |publisher=The Rocketman |date= |accessdate=2012-12-10}}</ref>
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| *rapid escape systems such as [[ejection seat]]s and [[launch escape system]]s
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| *[[space probe]]s
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| ==Design==
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| A rocket design can be as simple as a cardboard tube filled with [[black powder]], but to make an efficient, accurate rocket or missile involves overcoming a number of difficult problems. The main difficulties include cooling the combustion chamber, pumping the fuel (in the case of a liquid fuel), and controlling and correcting the direction of motion.<ref>{{Citation |author= Richard B. Dow | title=Fundamentals of Advanced Missiles |year=1958 |location=Washington (DC) |publisher=John Wiley & Sons |loc=58-13458}}</ref>
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| ===Components===
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| Rockets consist of a [[rocket propellant|propellant]], a place to put propellant (such as a [[propellant tank]]), and a [[rocket engine nozzle|nozzle]]. They may also have one or more [[rocket engine]]s, [[attitude control|directional stabilization device(s)]] (such as [[fins]], [[vernier engine]]s or engine [[gimbal]]s for [[thrust vectoring]], [[gyroscope]]s) and a structure (typically [[monocoque]]) to hold these components together. Rockets intended for high speed atmospheric use also have an [[aerodynamic]] fairing such as a [[nose cone]], which usually holds the payload.<ref>{{Citation |author= United States Congress. House Select Committee on Astronautics and Space Exploration |coauthor=Rand Corporation. | title=Space handbook: Astronautics and its applications : Staff report of the Select Committee on Astronautics and Space Exploration |url=http://www.hq.nasa.gov/office/pao/History/conghand/spcover.htm |chapter =4. Rocket Vehicles |chapterurl=http://www.hq.nasa.gov/office/pao/History/conghand/vehicles.htm |series= House document / 86th Congress, 1st session, no. 86 |year=1959 |location=Washington (DC) |publisher=U.S. G.P.O. |oclc=52368435}}</ref>
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| As well as these components, rockets can have any number of other components, such as wings ([[rocketplane]]s), [[parachute]]s, wheels ([[rocket car]]s), even, in a sense, a person ([[rocket belt]]). Vehicles frequently possess [[Automotive navigation system|navigation system]]s and [[guidance system]]s that typically use [[satellite navigation]] and [[inertial navigation system]]s.
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| ===Engines===
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| {{Main|Rocket engine}}
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| Rocket engines employ the principle of [[jet engine|jet propulsion]].<ref name="RPE7"/> The rocket engines powering rockets come in a great variety of different types, a comprehensive list can be found in [[rocket engine]]. Most current rockets are chemically powered rockets (usually [[internal combustion engines]],<ref>{{cite web|author=Charles Lafayette Proctor II |url=http://concise.britannica.com/ebc/article-9368065/internal-combustion-engine |title=internal combustion engines |publisher=Concise Britannica |date= |accessdate=2012-12-10}}</ref> but some employ a decomposing [[monopropellant]]) that emit a hot [[exhaust gas]]. A rocket engine can use gas propellants, [[Solid-fuel rocket|solid propellant]], [[liquid rocket|liquid propellant]], or a [[hybrid rocket|hybrid mixture of both solid and liquid]].<ref name="RPE7"/> Some rockets use heat or pressure that is supplied from a source other than the chemical reaction of propellant(s), such as [[steam rocket]]s, [[solar thermal rocket]]s, [[nuclear thermal rocket]] engines or simple pressurized rockets such as [[water rocket]] or [[cold gas thruster]]s.<ref name="RPE7"/> With combustive propellants a chemical reaction is initiated between the [[fuel]] and the [[oxidizer]] in the [[combustion]] chamber, and the resultant hot gases accelerate out of a [[rocket engine nozzle]] (or [[nozzle]]s) at the rearward-facing end of the rocket. The [[acceleration]] of these gases through the engine exerts force ("thrust") on the combustion chamber and nozzle, propelling the vehicle (according to [[Newton's Third Law]]).<ref name="RPE7"/> This actually happens because the force (pressure times area) on the combustion chamber wall is unbalanced by the nozzle opening; this is not the case in any other direction. The shape of the nozzle also generates force by directing the exhaust gas along the axis of the rocket.
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| ===Propellant===
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| {{Main|Rocket propellant}}
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| Rocket propellant is mass that is stored, usually in some form of [[propellant]] tank or casing, prior to being used as the propulsive mass that is ejected from a [[rocket engine]] in the form of a [[fluid]] [[jet (fluid)|jet]] to produce [[thrust]].<ref name="RPE7"/> For chemical rockets often the propellants are a fuel such as [[liquid hydrogen]] or [[kerosene]] burned with an oxidizer such as [[liquid oxygen]] or [[nitric acid]] to produce large volumes of very hot gas. The oxidiser is either kept separate and mixed in the combustion chamber, or comes premixed, as with solid rockets.
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| Sometimes the propellant is not burned but still undergoes a chemical reaction, and can be a 'monopropellant' such as [[hydrazine]], [[nitrous oxide]] or [[hydrogen peroxide]] that can be [[catalyst|catalytically]] decomposed to hot gas.
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| Alternatively, an inert propellant can be used that can be externally heated, such as in [[steam rocket]], [[solar thermal rocket]] or [[nuclear thermal rocket]]s.<ref name="RPE7"/>
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| For smaller, low performance rockets such as [[attitude control thruster]]s where high performance is less necessary, a pressurised fluid is used as propellant that simply escapes the spacecraft through a propelling nozzle.<ref name="RPE7"/>
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| ==Uses==
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| Rockets or other similar [[reaction engine|reaction devices]] carrying their own propellant must be used when there is no other substance (land, water, or air) or force ([[gravity]], [[magnetism]], [[light]]) that a [[vehicle]] may usefully employ for propulsion, such as in space. In these circumstances, it is necessary to carry all the [[propellant]] to be used.
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| However, they are also useful in other situations:
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| ===Military===
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| [[Image:Trident II missile image.jpg|upright|thumb|A [[Trident (missile)|Trident II missile]] launched from a [[Royal Navy]] [[Vanguard class submarine|''Vanguard'' class]] [[ballistic missile submarine]].]]
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| Some military weapons use rockets to propel [[warhead]]s to their targets. A rocket and its payload together are generally referred to as a ''[[missile]]'' when the weapon has a [[guidance system]] (not all missiles use rocket engines, some use other engines such as [[jet engine|jet]]s) or as a ''[[rocket (weapon)|rocket]]'' if it is unguided. Anti-tank and anti-aircraft missiles use rocket engines to engage targets at high speed at a range of several miles, while intercontinental ballistic missiles can be used to deliver multiple nuclear warheads from thousands of miles, and [[anti-ballistic missile]]s try to stop them.
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| ===Science and research===
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| [[Image:Bumper.jpg|thumb|left|upright|A [[Bumper (rocket)|Bumper]] sounding rocket]]
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| {{See also| Space probe}}
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| [[Sounding rocket]]s are commonly used to carry instruments that take readings from {{convert|50|km|mi|sp=us}} to {{convert|1500|km|mi|sp=us}} above the surface of the Earth, the altitudes between those reachable by [[weather balloon]]s and satellites.<ref>{{harvnb|Marconi|2004}}</ref>
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| Rocket engines are also used to propel [[rocket sled]]s along a rail at extremely high speed. The world record for this is Mach 8.5.<ref>{{cite web|title=Test sets world land speed record|url=http://www.af.mil/news/story.asp?storyID=123004755|publisher=www.af.mil|accessdate=2008-03-18}}</ref>
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| ===Spaceflight===
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| [[Image:Atlantis taking off on STS-27.jpg|thumb|{{OV|104}} during launch phase]]
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| {{Main| Spaceflight}}
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| Larger rockets are normally launched from a [[launch pad]] that provides stable support until a few seconds after ignition. Due to their high exhaust velocity—{{convert|2500|to|4500|m/s|km/h mph|abbr=on}} ([[Mach number|Mach]] ~10+)—rockets are particularly useful when very high speeds are required, such as orbital speed (Mach 24+<ref>{{Citation |last=Stillwell |first=Wendell H |title=X-15 Research Results |url=http://www.hq.nasa.gov/office/pao/History/SP-60/cover.html |chapter=Chapter 2: The First Hypersonic Airplane |chapterurl=http://history.nasa.gov/SP-60/ch-2.html |year=1964 |publisher=NASA }}</ref>). Spacecraft delivered into orbital trajectories become artificial [[satellites]], which are used for many commercial purposes. Indeed, rockets remain the only way to launch [[spacecraft]] into orbit and beyond.<ref>{{cite web|url=http://spaceflightnow.com/tracking/index.html |title=Spaceflight Now-worldwide launch schedule |publisher=Spaceflightnow.com |date= |accessdate=2012-12-10}}</ref> They are also used to rapidly accelerate spacecraft when they change orbits or de-orbit for [[landing]]. Also, a rocket may be used to soften a hard parachute landing immediately before touchdown (see [[retrorocket]]).
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| ===Rescue===
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| [[Image:Apollo Pad Abort Test -2.jpg|thumb|upright|Apollo LES [[pad abort test]] with [[Boilerplate (spaceflight)|boilerplate]] crew module.]]
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| Rockets were used to propel a line to a stricken ship so that a [[Breeches buoy]] can be used to [[rescue]] those on board. Rockets are also used to launch emergency flares.
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| Some crewed rockets, notably the [[Saturn V]]<ref>{{cite web|url=http://www.apollosaturn.com/asnr/escape.htm |title=Apollo launch escape subsystem |publisher=ApolloSaturn |date= |accessdate=2012-12-10}}</ref> and [[Soyuz (rocket)|Soyuz]]<ref name=soyuzt>{{cite web|url=http://www.astronautix.com/flights/soyzt101.htm |title=Soyuz T-10-1 "Launch vehicle blew up on pad at Tyuratam; crew saved by abort system" |publisher=Astronautix.com |date= |accessdate=2012-12-10}}</ref> have [[launch escape system]]s. This is a small, usually solid rocket that is capable of pulling the crewed capsule away from the main vehicle towards safety at a moments notice. These types of systems have been operated several times, both in testing and in flight, and operated correctly each time.{{Citation needed|for="correctly every time"|date=May 2010}}
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| Solid rocket propelled [[ejection seat]]s are used in many military aircraft to propel crew away to safety from a vehicle when flight control is lost.<ref>{{cite web|last=Bonsor |first=Kevin |url=http://science.howstuffworks.com/ejection-seat1.htm |title=Howstuff works ejection seats |publisher=Science.howstuffworks.com |date=2001-06-27 |accessdate=2012-12-10}}</ref>
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| ===Hobby, sport, and entertainment===
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| Hobbyists build and fly a wide variety of [[model rocket]]s. Many companies produce model rocket kits and parts but due to their inherent simplicity some hobbyists have been known to make rockets out of almost anything. Rockets are also used in some types of consumer and professional [[fireworks]]. [[Water rocket|A Water Powered Rocket]] is a type of model rocket using water as its reaction mass. The pressure vessel
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| (the engine of the rocket) is usually a used plastic soft drink bottle. The water is forced out by a pressurized gas, typically compressed air. It is an example of Newton's third law of motion.
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| [[Hydrogen peroxide]] rockets are used to power [[jet packs]],<ref>{{cite web|url=http://www.transchool.eustis.army.mil/museum/transportation%20museum/jetbelt.htm |title=jetbelt |publisher=Transchool.eustis.army.mil |date=1961-10-12 |accessdate=2010-02-08}}</ref> and have been used to power [[rocket car|cars]] and a rocket car holds the all time (albeit unofficial) [[drag racing]] record.<ref>{{cite web|url=http://www.eurodragster.com/news/news1002.asp?Story=oct30#oct30 |title=Sammy Miller |publisher=Eurodragster.com |date= |accessdate=2012-12-10}}</ref>
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| ==Noise==
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| For all but the very smallest sizes, rocket exhaust compared to other engines is generally very noisy. As the [[hypersonic]] exhaust mixes with the ambient air, [[shock wave]]s are formed. The [[sound intensity]] from these shock waves depends on the size of the rocket as well as the exhaust speed. The sound intensity of large, high performance rockets could potentially kill at close range.<ref name="CR566-3">{{harvnb|Potter|Crocker|1966}}{{Page needed|date=September 2010}}</ref>
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| The [[Space Shuttle]] generates over 200 [[dB(A)]] of noise around its base. A [[Saturn V]] launch was detectable on [[seismometer]]s a considerable distance from the launch site.
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| Noise is generally most intense when a rocket is close to the ground, since the noise from the engines radiates up away from the plume, as well as reflecting off the ground. This noise can be reduced somewhat by flame trenches with roofs, by water injection around the plume and by deflecting the plume at an angle.<ref name="CR566-3"/>
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| For crewed rockets various methods are used to reduce the sound intensity for the passengers, and typically the placement of the astronauts far away from the rocket engines helps significantly. For the passengers and crew, when a vehicle goes [[supersonic]] the sound cuts off as the sound waves are no longer able to keep up with the vehicle.<ref name="CR566-3"/>
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| ==Physics==
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| ===Operation===
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| [[File:Rocket engine.svg|thumb|right|A diagram of how a rocket engine works.]]
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| {{Main|Rocket engine}}
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| The [[Reaction (physics)|action]] of the rocket engine's [[combustion chamber]]s and [[Rocket engine nozzle|expansion nozzle]]s on a high pressure fluid is able to accelerate the fluid to extremely high speed, and conversely this exerts a large reactive thrust on the rocket (an equal and opposite reaction according to [[Newton's third law]]), which propels the rocket forwards.
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| [[File:Rocket thrust.svg|thumb|right|Rocket thrust is caused by pressures acting on the combustion chamber and nozzle]]
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| In a closed chamber, the pressures are equal in each direction and no acceleration occurs. If an opening is provided in the bottom of the chamber then the pressure is no longer acting on the missing section. This opening permits the exhaust to escape. The remaining pressures give a resultant thrust on the side opposite the opening, and these pressures are what push the rocket along.
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| Using a nozzle gives more force as well since the exhaust also presses on it as it expands outwards, roughly doubling the total force. If propellant gas is continuously added to the chamber then these pressures can be maintained for as long as propellant remains.<ref name="RPE7"/> Note that the pumps moving the propellant into the combustion chamber must maintain a pressure larger than the combustion chamber ---typically on the order of 100 atmospheres.
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| As a side effect, these pressures on the rocket also act on the exhaust in the opposite direction and accelerate this to very high speeds (according to [[Newton's Third Law]]).<ref name="RPE7"/> From the principle of [[conservation of momentum]] the speed of the exhaust of a rocket determines how much momentum increase is created for a given amount of propellant. This is called the rocket's ''[[specific impulse]]''.<ref name="RPE7"/> Because a rocket, propellant and exhaust in flight, without any external perturbations, may be considered as a closed system, the total momentum is always constant. Therefore, the faster the net speed of the exhaust in one direction, the greater the speed of the rocket can achieve in the opposite direction. This is especially true since the rocket body's mass is typically far lower than the final total exhaust mass.
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| As the remaining propellant decreases, rocket vehicles become lighter and their acceleration tends to increase until the propellant is exhausted. This means that much of the speed change occurs towards the end of the burn when the vehicle is much lighter.<ref name="RPE7"/>
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| | |
| ===Forces on a rocket in flight===
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| [[Image:Rktfor.gif|thumb|upright|left|Forces on a rocket in flight, rockets that must travel through the air are usually tall and thin as this shape gives a high [[ballistic coefficient]] and minimizes drag losses]]
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| The general study of the [[force]]s on a rocket is part of [[ballistics]]. The behaviour of spacecraft is studied in the subfield of [[astrodynamics]].
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| Flying rockets are primarily affected by the following:<ref>{{cite web|url=http://www.grc.nasa.gov/WWW/K-12/VirtualAero/BottleRocket/airplane/rktfor.html |title=NASA- Four forces on a model rocket |publisher=Grc.nasa.gov |date=2000-09-19 |accessdate=2012-12-10}}</ref>
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| *[[Thrust]] from the engine(s)
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| *[[Gravity]] from [[celestial bodies]]
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| *[[Drag (physics)|Drag]] if moving in atmosphere
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| *[[Lift (force)|Lift]]; usually relatively small effect except for [[rocket-powered aircraft]]
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| In addition, the [[centrifugal force (fictitious)|inertia and centrifugal pseudo-force]] can be significant due to the path of the rocket around the center of a celestial body; when high enough speeds in the right direction and altitude are achieved a stable [[orbit]] or [[escape velocity]] is obtained.
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| These forces, with a stabilizing tail (the ''[[empennage]]'') present will, unless deliberate control efforts are made, naturally cause the vehicle to follow a roughly [[parabola|parabolic]] trajectory termed a [[gravity turn]], and this trajectory is often used at least during the initial part of a [[rocket launch|launch]]. (This is true even if the rocket engine is [[Pendulum rocket fallacy|mounted at the nose]].) Vehicles can thus maintain low or even zero [[angle of attack]], which minimizes transverse [[stress (physics)|stress]] on the launch vehicle, permitting a weaker, and hence lighter, launch vehicle.<ref name=space-sourcebook>{{harvnb|Glasstone|1965}} [http://books.google.com/books?id=K6k0AAAAMAAJ&q=gravity+turn&dq=gravity+turn&pgis=1 p. 209.]</ref><ref name=thesis>{{harvnb|Callaway|2004|p=2}}</ref>
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| {{clear}}
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| ===Net thrust===
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| [[File:Rocket nozzle expansion.svg|thumb|Due to the supersonic nature of the exhaust jet the exit pressure can be different to ambient atmospheric pressure. ''Nozzles'' are said to be (top to bottom):<br />• '''Underexpanded''' (above ambient).<br />• '''Ambient'''.<br />• '''Overexpanded''' (below ambient).<br />• '''Grossly overexpanded'''.<br />If under or overexpanded then loss of efficiency occurs, grossly overexpanded nozzles lose less efficiency, but the exhaust jet is usually unstable. Rockets become progressively more underexpanded as they gain altitude. Note that almost all rocket engines are momentarily grossly overexpanded during startup in an atmosphere.<ref>{{harvnb|Huzel|Huang|1971}}{{Page needed|date=September 2010}}</ref>]]
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| {{For|a more detailed model of the net thrust of a rocket engine that includes the effect of atmospheric pressure|Rocket_engine#Net_thrust}}
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| A typical rocket engine can handle a significant fraction of its own mass in propellant each second, with the propellant leaving the nozzle at several kilometres per second. This means that the [[thrust-to-weight ratio]] of a rocket engine, and often the entire vehicle can be very high, in extreme cases over 100. This compares with other jet propulsion engines that can exceed 5 for some of the better<ref>{{cite web|url=http://www.geae.com/engines/military/j85/index.html |title=General Electric J85 |publisher=Geae.com |date=2012-09-07 |accessdate=2012-12-10}}</ref> engines.<ref>[http://www.thrustssc.com/thrustssc/Club/Secure/Arfons_Last_Stand.html ThrustSSC Mach 1 Club: ART ARFONS LAST STAND by Richard Noble] J-85 has "5.6 lbs of thrust for each pound of engine"</ref>
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| It can be shown that the net thrust of a rocket is:
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| :<math>F_n = \dot{m}\;v_{e}</math><ref>{{Harvnb|Sutton|2001}} eq-2-14</ref>
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| where:
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| :<math> \dot{m} =\,</math>propellant flow (kg/s or lb/s)
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| :<math>v_{e} =\,</math>the [[effective exhaust velocity]] (m/s or ft/s)
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| The effective exhaust velocity <math>v_{e}</math> is more or less the speed the exhaust leaves the vehicle, and in the vacuum of space, the effective exhaust velocity is often equal to the actual average exhaust speed along the thrust axis. However, the effective exhaust velocity allows for various losses, and notably, is reduced when operated within an atmosphere.
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| The rate of propellant flow through a rocket engine is often deliberately varied over a flight, to provide a way to control the thrust and thus the airspeed of the vehicle. This, for example, allows minimization of aerodynamic losses<ref name=maxq/> and can limit the increase of [[g-force|''g''-forces]] due to the reduction in propellant load.
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| ===Impulse===
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| {{Main|Impulse (physics)|l1=Impulse}}
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| The total impulse of a rocket burning its propellant is simply:<ref>{{Harvnb|Sutton|2001|p=27}}</ref>
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| :<math>I = \int F dt</math>
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| When there is fixed thrust, this is simply:
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| :<math>I = F t\;</math>
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| {{-}}
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| ===Specific impulse===
| |
| {{Main|specific impulse}}
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| {{stack|float=right|{{Specific impulse}}}}
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| As can be seen from the thrust equation the effective speed of the exhaust controls the amount of thrust produced from a particular quantity of fuel burnt per second.
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| | |
| An equivalent measure, the net thrust-seconds ([[Impulse (physics)|impulse]]) per weight unit of propellant expelled is called [[Specific impulse|specific Impulse]], <math>I_{sp}</math>, and this is one of the most important figures that describes a rocket's performance. It is defined such that it is related to the effective exhaust velocity by:
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| :<math>v_e = I_{sp} \cdot g_0</math><ref>{{Harvnb|Sutton|2001|p=29}}</ref>
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| where:
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| :<math>I_{sp}</math> has units of seconds
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| :<math>g_0</math> is the acceleration at the surface of the Earth
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| | |
| Thus, the greater the specific impulse, the greater the net thrust and performance of the engine. <math>I_{sp}</math> is determined by measurement while testing the engine. In practice the effective exhaust velocities of rockets varies but can be extremely high, ~4500 m/s, about 15 times the sea level speed of sound in air.
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| ===Delta-v (rocket equation)===
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| [[Image:Delta-Vs for inner Solar System.svg|thumb|upright|A map of approximate [[Delta-v]]'s around the solar system between Earth and [[Mars]]<ref>{{cite web|url=http://www.pma.caltech.edu/~chirata/deltav.html |title=table of cislunar/mars delta-vs |archiveurl=http://web.archive.org/web/20070701211813/http://www.pma.caltech.edu/~chirata/deltav.html |archivedate=2007-07-01}}</ref><ref>{{cite web|url=http://www.strout.net/info/science/delta-v/intro.html |title=cislunar delta-vs |publisher=Strout.net |date= |accessdate=2012-12-10}}</ref>]]
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| {{Main|Tsiolkovsky rocket equation}}
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| The [[delta-v]] capacity of a rocket is the theoretical total change in velocity that a rocket can achieve without any external interference (without air drag or gravity or other forces).
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| When <math>v_e</math> is constant, the delta-v that a rocket vehicle can provide can be calculated from the [[Tsiolkovsky rocket equation]]:<ref>{{cite web|url=http://www.projectrho.com/rocket/rocket3c.html |title=Choose Your Engine |publisher=Projectrho.com |date=2012-06-01 |accessdate=2012-12-10}}</ref>
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| :<math>\Delta v\ = v_e \ln \frac {m_0} {m_1}</math>
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| where:
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| :<math>m_0</math> is the initial total mass, including propellant, in kg (or lb)
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| :<math>m_1</math> is the final total mass in kg (or lb)
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| :<math>v_e</math> is the effective exhaust velocity in m/s (or ft/s)
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| :<math>\Delta v\ </math> is the delta-v in m/s (or ft/s)
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| When launched from the Earth practical delta-v's for a single rockets carrying payloads can be a few km/s. Some theoretical designs have rockets with delta-v's over 9 km/s.
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| The required delta-v can also be calculated for a particular manoeuvre; for example the delta-v to launch from the surface of the Earth to [[Low earth orbit]] is about 9.7 km/s, which leaves the vehicle with a sideways speed of about 7.8 km/s at an altitude of around 200 km. In this manoeuvre about 1.9 km/s is lost in [[air drag]], [[gravity drag]] and [[potential energy|gaining altitude]].
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| The ratio <math>\frac {m_0} {m_1}</math> is sometimes called the ''mass ratio''.
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| ===Mass ratios===
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| [[File:Rocket mass ratio versus delta-v.svg|thumb|The Tsiolkovsky rocket equation gives a relationship between the mass ratio and the final velocity in multiples of the exhaust speed]]
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| {{Main|mass ratio}}
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| Almost all of a launch vehicle's mass consists of propellant.<ref>{{cite web|url=http://www-istp.gsfc.nasa.gov/stargaze/Srockhis.htm |title=The Evolution of Rockets |publisher=Istp.gsfc.nasa.gov |date= |accessdate=2012-12-10}}</ref> Mass ratio is, for any 'burn', the ratio between the rocket's initial mass and the mass after.<ref>{{cite web|url=http://exploration.grc.nasa.gov/education/rocket/rktwtp.html |title=Rocket Mass Ratios |publisher=Exploration.grc.nasa.gov |date= |accessdate=2012-12-10}}</ref> Everything else being equal, a high mass ratio is desirable for good performance, since it indicates that the rocket is lightweight and hence performs better, for essentially the same reasons that low weight is desirable in sports cars.
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| Rockets as a group have the highest [[thrust-to-weight ratio]] of any type of engine; and this helps vehicles achieve high [[mass ratio]]s, which improves the performance of flights. The higher the ratio, the less engine mass is needed to be carried. This permits the carrying of even more propellant, enormously improving the delta-v. Alternatively, some rockets such as for rescue scenarios or racing carry relatively little propellant and payload and thus need only a lightweight structure and instead achieve high accelerations. For example, the Soyuz escape system can produce 20g.<ref name=soyuzt/>
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| Achievable mass ratios are highly dependent on many factors such as propellant type, the design of engine the vehicle uses, structural safety margins and construction techniques.
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| The highest mass ratios are generally achieved with liquid rockets, and these types are usually used for [[orbital launch vehicle]]s, a situation which calls for a high delta-v. Liquid propellants generally have densities similar to water (with the notable exceptions of [[liquid hydrogen]] and [[Liquid methane rocket fuel|liquid methane]]), and these types are able to use lightweight, low pressure tanks and typically run high-performance [[turbopumps]] to force the propellant into the combustion chamber.
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| Some notable mass fractions are found in the following table (some aircraft are included for comparison purposes):
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| {{Mass fraction table}}
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| ===Staging===
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| [[Image:Artistsconcept separation.jpg|thumb|upright|Staging involves dropping off unnecessary parts of the rocket to reduce mass]]
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| [[Image:Ap6-68-HC-191.jpg|thumb|upright|[[Apollo 6]] while dropping the interstage ring]]
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| {{Main|Multistage rocket}}
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| Often, the required velocity (delta-v) for a mission is unattainable by any single rocket because the [[propellant]], tankage, structure, [[guidance system|guidance]], valves and engines and so on, take a particular minimum percentage of take-off mass that is too great for the propellant it carries to achieve that delta-v.
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| For example the first stage of the Saturn V, carrying the weight of the upper stages, was able to achieve a [[mass ratio]] of about 10, and achieved a specific impulse of 263 seconds. This gives a delta-v of around 5.9 km/s whereas around 9.4 km/s delta-v is needed to achieve orbit with all losses allowed for.
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| This problem is frequently solved by [[staging (rocketry)|staging]] — the rocket sheds excess weight (usually empty tankage and associated engines) during launch. Staging is either ''serial'' where the rockets light after the previous stage has fallen away, or ''parallel'', where rockets are burning together and then detach when they burn out.<ref name="NASAstaging">{{harvnb|NASA|2006}}</ref>
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| The maximum speeds that can be achieved with staging is theoretically limited only by the speed of light. However the payload that can be carried goes down geometrically with each extra stage needed, while the additional delta-v for each stage is simply additive.
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| ===Acceleration and thrust-to-weight ratio===
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| {{Main|thrust-to-weight ratio}}
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| From Newton's second law, the acceleration, <math>a</math>, of a vehicle is simply:
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| | |
| :<math>a = \frac {F_n} {m}</math>
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| Where m is the instantaneous mass of the vehicle and <math>F_n</math> is the net force acting on the rocket (mostly thrust but air drag and other forces can play a part.)
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| Typically, the acceleration of a rocket increases with time (if the thrust stays the same) as the weight of the rocket decreases as propellant is burned, but the thrust can be throttled to offset or vary this if needed. Discontinuities in acceleration also occur when stages burn out, often starting at a lower acceleration with each new stage firing.
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| Peak accelerations can be increased by designing the vehicle with a reduced mass, usually achieved by a reduction in the fuel load and tankage and associated structures, but obviously this reduces range, delta-v and burn time. Still, for some applications that rockets are used for, a high peak acceleration applied for just a short time is highly desirable.
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| The minimal mass of vehicle consists of a rocket engine with minimal fuel and structure to carry it. In that case the [[thrust-to-weight ratio]]{{#tag:ref|“thrust-to-weight ratio F/W<sub>g</sub> is a dimensionless parameter that is identical to the acceleration of the rocket propulsion system (expressed in multiples of g<sub>0</sub>) ... in a gravity-free vacuum”<ref name="suttontw">{{Harvnb|Sutton|2001|p=442}}</ref>|group=nb}} of the rocket engine limits the maximum acceleration that can be designed. It turns out that rocket engines generally have truly excellent thrust to weight ratios (137 for the [[NK-33]] engine,<ref>{{cite web|url=http://www.astronautix.com/engines/nk33.htm |title=Astronautix NK-33 entry |publisher=Astronautix.com |date=2006-11-08 |accessdate=2012-12-10}}</ref> some solid rockets are over 1000<ref name="suttontw"/>), and nearly all really [[g-force|high-g]] vehicles employ or have employed rockets.
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| The high accelerations that rockets naturally possess means that rocket vehicles are often capable of [[VTOL|vertical takeoff]]; this can be done provided a vehicle's engines provide more than the local gravitational acceleration away from the Earth or gravity source.
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| | |
| ===Drag===
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| Drag is a force opposite to the direction of the rocket's motion. This decreases acceleration of the vehicle and produces structural loads. Deceleration force for fast-moving rockets are calculated using the [[drag equation]].
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| Drag can be minimised by an aerodynamic [[nose cone]] and by using a shape with a high ballistic coefficient (the "classic" rocket shape—long and thin), and by keeping the rocket's [[angle of attack]] as low as possible.
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| During a rocket launch, as the vehicle speed increases, and the atmosphere thins, there is a point of maximum aerodynamic drag called [[Max Q]]. This determines the minimum aerodynamic strength of the vehicle, as the rocket must avoid [[buckling]] under these forces.<ref name=maxq>{{cite web|url=http://www.aerospaceweb.org/question/aerodynamics/q0025.shtml |title=Space Shuttle Max-Q |publisher=Aerospaceweb |date=2001-05-06 |accessdate=2012-12-10}}</ref>
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| ===Energy===
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| | |
| ====Energy efficiency====
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| {{Main|propulsive efficiency}}
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| Rocket launch vehicles take-off with a great deal of flames, noise and drama, and it might seem obvious that they are grievously inefficient. However, while they are far from perfect, their energy efficiency is not as bad as might be supposed.
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| The energy density of a typical rocket propellant is often around one-third that of conventional hydrocarbon fuels; the bulk of the mass is (often relatively inexpensive) oxidizer. Nevertheless, at take-off the rocket has a great deal of energy in the fuel and oxidizer stored within the vehicle. It is of course desirable that as much of the energy of the propellant end up as [[kinetic energy|kinetic]] or [[potential energy]] of the body of the rocket as possible.
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| Energy from the fuel is lost in air drag and [[gravity drag]] and is used for the rocket to gain altitude and speed. However, much of the lost energy ends up in the exhaust.<ref name="RPE"/>
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| | |
| In a chemical propulsion device, the engine efficiency is simply the ratio of the kinetic power of the exhaust gases and the power available from the chemical reaction:<ref name="RPE">{{Harvnb|Sutton|2001|pp=37–38}}</ref>
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| | |
| :<math>\eta_c= \frac {\frac {1} {2}\dot{m}v_e^2} {\eta_{combustion} P_{chem} }</math>
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| | |
| 100% efficiency within the engine (engine efficiency <math>\eta_c = 100%</math>) would mean that all the heat energy of the combustion products is converted into kinetic energy of the jet. [[Heat Engine#Efficiency|This is not possible]], but the near-adiabatic [[rocket engine nozzle|high expansion ratio nozzles]] that can be used with rockets come surprisingly close: when the nozzle expands the gas, the gas is cooled and accelerated, and an energy efficiency of up to 70% can be achieved. Most of the rest is heat energy in the exhaust that is not recovered.<ref name="RPE"/> The high efficiency is a consequence of the fact that rocket combustion can be performed at very high temperatures and the gas is finally released at much lower temperatures, and so giving good [[Carnot efficiency]].
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| However, engine efficiency is not the whole story. In common with the other [[jet engine|jet-based engines]], but particularly in rockets due to their high and typically fixed exhaust speeds, rocket vehicles are extremely inefficient at low speeds irrespective of the engine efficiency. The problem is that at low speeds, the exhaust carries away a huge amount of [[kinetic energy]] rearward. This phenomenon is termed [[propulsive efficiency]] (<math>\eta_p</math>).<ref name="RPE"/>
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| However, as speeds rise, the resultant exhaust speed goes down, and the overall vehicle energetic efficiency rises, reaching a peak of around 100% of the engine efficiency when the vehicle is travelling exactly at the same speed that the exhaust is emitted. In this case the exhaust would ideally stop dead in space behind the moving vehicle, taking away zero energy, and from conservation of energy, all the energy would end up in the vehicle. The efficiency then drops off again at even higher speeds as the exhaust ends up travelling forwards- trailing behind the vehicle.
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| [[File:Average propulsive efficiency of rockets.png|thumb|upright=1.5|Plot of instantaneous propulsive efficiency (blue) and overall efficiency for a rocket accelerating from rest (red) as percentages of the engine efficiency]]From these principles it can be shown that the propulsive efficiency <math>\eta_p</math> for a rocket moving at speed <math>u</math> with an exhaust velocity <math>c</math> is:
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| :<math>\eta_p= \frac {2 \frac {u} {c}} {1 + ( \frac {u} {c} )^2 }</math><ref name="RPE"/>
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| | |
| And the overall (instantaneous) energy efficiency <math>\eta</math> is:
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| :<math>\eta= \eta_p \eta_c</math>
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| For example, from the equation, with an <math>\eta_c</math> of 0.7, a rocket flying at Mach 0.85 (which most aircraft cruise at) with an exhaust velocity of Mach 10, would have a predicted overall energy efficiency of 5.9%, whereas a conventional, modern, air-breathing jet engine achieves closer to 35% efficiency. Thus a rocket would need about 6x more energy; and allowing for the specific energy of rocket propellant being around one third that of conventional air fuel, roughly 18x more mass of propellant would need to be carried for the same journey. This is why rockets are rarely if ever used for general aviation.
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| Since the energy ultimately comes from fuel, these considerations mean that rockets are mainly useful when a very high speed is required, such as [[ICBM]]s or [[orbital spaceflight|orbital launch]]. For example [[NASA]]'s [[space shuttle]] fires its engines for around 8.5 minutes, consuming 1,000 tonnes of solid propellant (containing 16% aluminium) and an additional 2,000,000 litres of liquid propellant (106,261 kg of [[liquid hydrogen]] fuel) to lift the 100,000 kg vehicle (including the 25,000 kg payload) to an altitude of 111 km and an orbital [[velocity]] of 30,000 km/h. At this altitude and velocity, the vehicle has a kinetic energy of about 3 TJ and a potential energy of roughly 200 GJ. Given the initial energy of 20 TJ,{{#tag:ref|The energy density is 31MJ per kg for aluminum and 143 MJ/kg for liquid hydrogen, this means that the vehicle consumes around 5 TJ of solid propellant and 15 TJ of hydrogen fuel.|group=nb}} the Space Shuttle is about 16% energy efficient at launching the orbiter.
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| Thus jet engines, with a better match between speed and jet exhaust speed (such as [[turbofans]]—in spite of their worse <math>\eta_c</math>)—dominate for subsonic and supersonic atmospheric use, while rockets work best at hypersonic speeds. On the other hand, rockets serve in many short-range ''relatively'' low speed military applications where their low-speed inefficiency is outweighed by their extremely high thrust and hence high accelerations.
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| ====Oberth effect====
| |
| {{Main|Oberth effect}}
| |
| One subtle feature of rockets relates to energy. A rocket stage, while carrying a given load, is capable of giving a particular [[delta-v]]. This delta-v means that the speed increases (or decreases) by a particular amount, independent of the initial speed. However, because [[kinetic energy]] is a square law on speed, this means that the faster the rocket is travelling before the burn the more [[orbital energy]] it gains or loses.
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| This fact is used in interplanetary travel. It means that the amount of delta-v to reach other planets, over and above that to reach escape velocity can be much less if the delta-v is applied when the rocket is travelling at high speeds, close to the Earth or other planetary surface; whereas waiting until the rocket has slowed at altitude multiplies up the effort required to achieve the desired trajectory.
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| ==Safety, reliability and accidents==
| |
| [[Image:Challenger explosion.jpg|thumb|upright|[[Space Shuttle Challenger]] was torn apart 73 seconds after launch after hot gases escaped the [[Solid rocket booster|SRBs]], causing the breakup of the Shuttle stack]]
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| {{See also| List of spaceflight-related accidents and incidents}}
| |
| The reliability of rockets, as for all physical systems, is dependent on the quality of engineering design and construction.
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| | |
| Because of the enormous chemical energy in [[rocket propellant]]s (greater energy by weight than explosives, but lower than [[gasoline]]), consequences of accidents can be severe. Most space missions have some issues.<ref name="Janes">{{cite web|url=http://www.janes.com/aerospace/civil/news/jsd/jsd030203_3_n.shtml|title=A brief history of space accidents|date=2003-02-03|publisher=Jane's Civil Aerospace|accessdate=2010-04-24|archiveurl=http://web.archive.org/web/20030204073904/http://www.janes.com/aerospace/civil/news/jsd/jsd030203_3_n.shtml|archivedate=2003-02-04}}</ref> In 1986, following the [[Space Shuttle Challenger Disaster]], American Physicist [[Richard Feynman]], having served on the [[Rogers Commission]] estimated that the chance of an unsafe condition for a launch of the Shuttle was very roughly 1%;<ref>{{cite web|url=http://science.ksc.nasa.gov/shuttle/missions/51-l/docs/rogers-commission/Appendix-F.txt |title=Rogers commission Appendix F |date= |accessdate=2012-12-10}}</ref> more recently the historical per person-flight risk in orbital spaceflight has been calculated to be around 2%<ref>{{cite web|url=http://www.space.com/missionlaunches/spacetourism_future_040930.html |title=Going Private: The Promise and Danger of Space Travel By Tariq Malik |publisher=Space.com |date=2004-09-30 |accessdate=2012-12-10}}</ref> or 4%.<ref name=SpaceReview>{{cite web|url=http://www.thespacereview.com/article/36/2|title=Weighing the risks of human spaceflight|publisher=[[The Space Review]]|date=21 July 2003|accessdate=1 December 2010}}</ref>
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| ==Costs and economics==
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| The costs of rockets can be roughly divided into propellant costs, the costs of obtaining and/or producing the 'dry mass' of the rocket and the costs of any required support equipment and facilities.<ref name=aday>[http://www.fourmilab.ch/documents/rocketaday.html A Rocket a Day Keeps the High Costs Away] by John Walker September 27, 1993</ref>
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| Most of the takeoff mass of a rocket is normally propellant. However propellant is seldom more than a few times more expensive than gasoline per kg (as of 2009 gasoline is about $1/kg or less), and although substantial amounts are needed, for all but the very cheapest rockets it turns out that the propellant costs are usually comparatively small, although not completely negligible.<ref name=aday/> With liquid oxygen costing $0.15 per kilogram and liquid hydrogen $2.20 per kilogram, the [[Space Shuttle]] has a liquid propellant expense of approximately $1.4 million for each launch that costs $450 million from other expenses (with 40% of the mass of propellants used by it being liquids in the [[external fuel tank]], 60% solids in the [[Space Shuttle Solid Rocket Booster|SRBs]]).<ref>{{cite web|url=http://www-pao.ksc.nasa.gov/kscpao/nasafact/pdf/ssp.pdf |title=Space Shuttle Use of Propellants and Fluids |publisher=Nasa.gov |date= |accessdate=2011-04-30}}</ref><ref>{{cite web|url=http://www-pao.ksc.nasa.gov/nasafact/count2.htm |title=NASA Launch Vehicles and Facilities |publisher=Nasa.gov |date= |accessdate=2011-04-30}}</ref><ref>{{cite web|url=http://www.nasa.gov/centers/kennedy/about/information/shuttle_faq.html |title=NASA - Space Shuttle and International Space Station |publisher=Nasa.gov |date= |accessdate=2011-04-30}}</ref>
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| Even though a rocket's non-propellant, dry mass is often only between 5-20% of total mass,<ref>{{cite web|url=http://www.spacetethers.com/massfraction.html |title=Mass Fraction |publisher=Andrews Space and Technology (original figure source) |date= |accessdate=2011-04-30}}</ref> nevertheless this cost dominates. For hardware with the performance used in orbital [[launch vehicle]]s, expenses of $2000–$10,000+ per kilogram of [[dry weight]] are common, primarily from engineering, fabrication, and testing; raw materials amount to typically around 2% of total expense.<ref>Regis, Ed (1990),''Great Mambo Chicken And The Transhuman Condition: Science Slightly Over The Edge'', Basic Books, ISBN 0-201-56751-2. [http://groups.google.com/group/sci.space/browse_thread/thread/dcc29174a504c200/7e68102f0a014325?hl=en&ie=UTF-8&oe=utf-8&q Excerpt online]</ref><ref name = CheapRockets>[[:File:LEOonthecheap.pdf|U.S. Air Force Research Report No. AU-ARI-93-8: LEO On The Cheap]]. Retrieved April 29, 2011.</ref> For most rockets except reusable ones (shuttle engines) the engines need not function more than a few minutes, which simplifies design.
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| Extreme performance requirements for rockets reaching orbit correlate with high cost, including intensive quality control to ensure reliability despite the limited [[safety factor]]s allowable for weight reasons.<ref name=CheapRockets/> Components produced in small numbers if not individually machined can prevent
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| amortization of R&D and facility costs over mass production to the degree seen in more pedestrian manufacturing.<ref name=CheapRockets/> Amongst liquid-fueled rockets, complexity can be influenced by how much hardware must be lightweight, like pressure-fed engines can have two orders of magnitude lesser part count than pump-fed engines but lead to more weight by needing greater tank pressure, most often used in just small maneuvering thrusters as a consequence.<ref name=CheapRockets/>
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| To change the preceding factors for orbital launch vehicles, proposed methods have included mass-producing simple rockets in large quantities or on large scale,<ref name=aday/> or developing [[reusable launch system|reusable rockets]] meant to fly very frequently to amortize their up-front expense over many payloads, or
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| reducing rocket performance requirements by constructing a hypothetical [[non-rocket spacelaunch]] system for part of the velocity to orbit (or all of it but with
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| most methods involving some rocket use).
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| | |
| The costs of support equipment, range costs and launch pads generally scale up with the size of the rocket, but vary less with launch rate, and so may be considered to be approximately a fixed cost.<ref name=aday/>
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| | |
| Rockets in applications other than launch to orbit (such as military rockets and [[JATO|rocket-assisted take off]]), commonly not needing comparable performance and sometimes mass-produced, are often relatively inexpensive.
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| | |
| ==See also==
| |
| {{Portal| Spaceflight }}
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| <div style="-moz-column-count:2; column-count:2;">
| |
| '''Lists'''
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| * [[Chronology of Pakistan's rocket tests]]
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| * [[List of rockets (disambiguation)|List of rockets]]
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| * [[Timeline of rocket and missile technology]]
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| * [[Timeline of spaceflight]]
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| | |
| '''General rocketry'''
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| * [[Aircraft]]
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| * [[Ammonium Perchlorate Composite Propellant]]—Most common solid rocket fuel
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| * [[Astrodynamics]] the study of spaceflight trajectories
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| * [[Bipropellant rocket]]—two-part liquid or gaseous fuelled rocket
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| * [[Hot Water Rocket|Hot Water rocket]]—powered by boiling water
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| * [[Hybrid rocket]]—solid rocket burnt by second fluid propellant
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| * [[Gantry (rocketry)|Gantry]]
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| * [[Pendulum rocket fallacy]]—an instability of rockets
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| * [[Pulsed Rocket Motors]]—solid rocket that burns in segments
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| * [[Rocket engine]]
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| * [[Rocket engine nozzles]]—De Laval nozzles
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| * [[Rocket fuel]]
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| * [[Rocket launch]]
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| * [[Rocket launch site]]
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| * [[Rocket propellant]]
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| * [[Rocket garden]] a place for viewing unlaunched rockets
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| * [[Solid rocket]]
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| * [[Sounding rocket]]
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| * [[Space Shuttle program]]
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| * [[Spacecraft]]
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| * [[Spacecraft propulsion]]—describes many different propulsion systems for spacecraft
| |
| * [[Spaceflight]]
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| * [[Tripropellant rocket]]—variable propellant mixes can improve performance
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| * [[Tsiolkovsky rocket equation]]—equation describing rocket performance
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| * [[Variable-mass system]]—the form of Newton's second law used for describing rocket motion
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| | |
| '''Recreational rocketry'''
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| * [[Balloon rocket]]
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| * [[High-powered rocket]]
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| * [[Model rocket]]—small hobby rocket
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| * [[National Association of Rocketry]]
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| * [[Tripoli Rocketry Association]]
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| * [[Water rocket]]—toy rocket launched for recreational purposes using water as propellant
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| | |
| '''Recreational pyrotechnic rocketry'''
| |
| * [[Bottle rocket]]—small firework type rocket often launched from bottles
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| * [[Skyrocket]]—fireworks that typically explode at apogee
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| | |
| '''Weaponry'''
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| * [[:Category:Air-to-ground rockets|Air-to-ground rockets]]
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| * [[Fire Arrow]]—one of the earliest types of rocket
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| * [[Katyusha rocket launcher]]—rack mounted rocket
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| * [[Rocket-propelled grenade]]—military use of rockets
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| * [[Shin Ki Chon]]—Korean variation of the Chinese fire arrow
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| * [[VA-111 Shkval]]—Russian rocket-propelled [[supercavitation]] torpedo
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| | |
| '''Rockets for Research'''
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| * [[Disappearing rocket]]—rocket that disintegrate if fired from the ground for safety reasons
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| * [[Rocket plane]]—winged aircraft powered by rockets
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| * [[Rocket sled]]—used for high speeds along ground
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| * [[Sounding rocket]]—suborbital rocket used for atmospheric and other research
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| | |
| '''Misc'''
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| * [[Equivalence principle]]—Einstein was able to show that the effects of gravity were completely equivalent to a rocket's acceleration in any small region of space
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| * [[Rocket Festival]]—Tradition bamboo rockets of Laos and Northeastern Thailand
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| * [[Rocket mail]]—an ill-fated attempt to commercialize rocketry
| |
| </div>
| |
| {{-}}
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| | |
| ==Notes==
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| ;Footnotes
| |
| {{Reflist|2|group=nb}}
| |
| | |
| ;Citations
| |
| {{Reflist|2}}
| |
| | |
| ==References==
| |
| {{Refbegin|2}}
| |
| *{{Citation |last1=Allen |first1= H. Julian |last2=Eggers |first2=A. J. |url=http://naca.central.cranfield.ac.uk/reports/1958/naca-report-1381.pdf |title=A Study of the Motion and Aerodynamic Heating of Ballistic Missiles Entering the Earth's Atmosphere at High Supersonic Speeds |publisher= NACA |year=1958 |oclc=86134556}}
| |
| *{{Citation | last = Baker | first = A. D. | title = Combat Fleets of the World 2000-2001 | publisher = US Naval Institute Press | location = Annapolis | year = 2000 | isbn = 978-1-55750-197-4 }}
| |
| *{{Citation |last=Béon|first=Yves |others=translated from the French '''La planète Dora''' by Béon & Richard L. Fague |title=Planet Dora: A Memoir of the Holocaust and the Birth of the Space Age|year=1997 |publisher=Westview Press, Div. of Harper Collins|isbn=0-8133-3272-9 }}
| |
| *{{Citation | last = Buchanan | first = Brenda | title = Gunpowder, Explosives and the State |url= http://books.google.com/?id=7n6Cg9znFrUC&printsec=frontcover | publisher = Ashgate | location = Aldershot | year = 2006 | isbn = 978-0-7546-5259-5 }}
| |
| *{{Citation | first = David W. | last = Callaway | title = Coplanar Air Launch with Gravity-Turn Launch Trajectories | journal = Masters Thesis |date=March 2004 | url = https://research.maxwell.af.mil/papers/ay2004/afit/AFIT-GAE-ENY-04-M04.pdf|format=PDF}}
| |
| *{{Citation | last = Chase | first = Kenneth | title = Firearms : A global history to 1700 | url=http://books.google.com/?id=esnWJkYRCJ4C&printsec=frontcover |publisher = Cambridge University Press | location = Cambridge | year = 2003 | isbn = 978-0-521-82274-9 }}
| |
| *{{Citation | last = Clary | first = David | title = Rocket Man | publisher = Theia | location = New York | year = 2003 | isbn = 978-0-7868-6817-9 }}
| |
| *{{Citation | last = Crosby | first = Alfred W. | title = Throwing Fire: Projectile Technology Through History | year = 2002 | publisher = Cambridge University Press | location = Cambridge | isbn = 0-521-79158-8}}
| |
| *{{Citation |last=Esnault-Pelterie |first=Robert |title=Considerations sur les resultats d'un allegement indefini des moteurs |journal=Journal de physique theorique et appliquee |location=Paris |year=1913 |oclc=43942743 |language=French }}
| |
| *{{Citation |author=GAO |title= Cost Benefit Analysis Used in Support of the Space Shuttle Program |url=http://archive.gao.gov/f0302/096542.pdf |location= Washington, DC |publisher= General Accounting Office, US Government |year= 1972 }}
| |
| *{{Citation | last = Glasstone | first = Samuel | title = Sourcebook on the Space Sciences | publisher = D. Van Nostrand Company | year = 1965 |oclc=232378}}
| |
| *{{Citation | last = Goddard | first = Robert |title = A Method of Reaching Extreme Altitudes |url= http://www.clarku.edu/research/archives/pdf/ext_altitudes.pdf |year=1919 |oclc=3430998 |authorlink=Robert Goddard}}
| |
| *{{Citation | last = Goddard | first = Robert | title = Rockets | publisher = Dover Publications | location = New York | year = 2002 | isbn = 978-0-486-42537-5 }}
| |
| *{{Citation |last=Hansen |first=James R. |year=1987 |url=http://history.nasa.gov/SP-4305/sp4305.htm |title=Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917-1958. |work=The NASA History Series, sp-4305 |publisher=NASA |oclc=246830126}}
| |
| *{{Citation |last=Harford |first=James |authorlink= |coauthors= |others= |title=Korolev: How One Man Masterminded the Soviet Drive to Beat America to the Moon |year=1997 |publisher=John Wiley & Sons |location= |isbn=0-471-14853-9 }}
| |
| *{{Citation |last=Hassan |first=Ahmad Y |url= http://www.history-science-technology.com/Articles/articles%202.htm |title=Gunpowder Composition for Rockets and Cannon in Arabic Military Treatises In Thirteenth and Fourteenth Centuries |accessdate=2008-03-29 |authorlink=Ahmad Y Hassan |work=History of Science and Technology in Islam |year=a}}
| |
| *{{Citation |last=Hassan |first=Ahmad Y |url= http://www.history-science-technology.com/Articles/articles%2072.htm |title=Transfer Of Islamic Technology To The West, Part III: Technology Transfer in the Chemical Industries |accessdate=2008-03-29 |authorlink=Ahmad Y Hassan |work=History of Science and Technology in Islam |year=b}}
| |
| *{{Citation |last=Houchin |first=Roy |title=U.S. Hypersonic Research and Development: The Rise and Fall of Dyna-Soar, 1944–1963 |year=2006 |publisher=Routledge |location=New York |isbn=0-415-36281-4}}
| |
| *{{Citation |last=Hunt |first=Linda |title=Secret Agenda: The United States Government, Nazi Scientists, and Project Paperclip, 1945 to 1990 |year=1991 |publisher=St.Martin's Press |location=New York |isbn=0-312-05510-2}}
| |
| *{{Citation|last1=Huzel |first1=D. K. |last2=Huang |first2=D. H. |title=NASA SP-125, Design of Liquid Propellant Rocket Engines |edition=2nd |publisher=NASA |year=1971 |url=http://ntrs.nasa.gov/search.jsp?Ntt=sp-125&Ntk=all&Ntx=mode}}
| |
| *{{Citation |last=Johnson |first= |title=Contents and commentary on William Moore's a treatise on the motion of rockets and an essay on naval gunnery |journal=International Journal of Impact Engineering |volume=16 |issue=3 |date = June 1995|oclc=105570427}}
| |
| *{{Citation | last = Marconi | first = Elaine M. | date = April 12, 2004 | url = http://www.nasa.gov/missions/research/f_sounding.html | title = What is a Sounding Rocket? | work = Research Aircraft | publisher = NASA | accessdate = October 10, 2006}}
| |
| *{{Citation |author=NASA |url=http://exploration.grc.nasa.gov/education/rocket/rktstage.html |title=Rocket staging |accessdate=2009-06-28 |publisher=NASA |work=Beginner's Guide to Rockets |year=2006}}
| |
| *{{Citation | last = Needham | first = Joseph | title = Science and Civilisation in China |url=http://books.google.com/?id=BZxSnd2Xyb0C&printsec=frontcover | publisher = Cambridge University Press | location = Cambridge | year = 1986 | isbn = 978-0-521-30358-3 }}
| |
| *{{Citation |last=Nowak |first=Tadeusz |title=Kazimierz Siemienowicz ok.1600-ok.1951 |year=1969 |publisher=MON Press |location=Warsaw |oclc=254130686 |language=Polish}}
| |
| *{{Citation | last = Polmar | first = Norman | title = Cold War Submarines | publisher = Brassey's | location = Washington | year = 2004 | isbn = 978-1-57488-594-1 }}
| |
| *{{Citation |last1=Potter |first1=R.C |last2=Crocker |title=Acoustic Prediction Methods for Rocket Engines, Including the Effects of Clustered Engines and Deflected Exhaust Flow, CR-566 |url=http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19660030602_1966030602.pdf |location=Washington, D.C. |publisher=NASA |year=1966 |oclc=37049198|first2=M.J }}
| |
| *{{Citation |author=Space History Division |url=http://www.nasm.si.edu/research/dsh/artifacts/RM-Hale24pdr.htm |archiveurl=http://web.archive.org/web/20070818125248/http://www.nasm.si.edu/research/dsh/artifacts/RM-Hale24pdr.htm |archivedate=2007-08-18 |title=Hale 24-Pounder Rocket |publisher=Smithsonian National Air and Space Museum |year=1999}}
| |
| *{{Cite DNB|authorlink=Henry Morse Stephens|first=Henry Morse|last=Stephens|wstitle=Congreve, William (1772-1828)|volume=12|page=9|ref=harv}}
| |
| *{{Citation | last = Sutton | first = George | title = Rocket Propulsion Elements |edition=7th |url=http://books.google.com/?id=LQbDOxg3XZcC&printsec=frontcover | publisher = John Wiley & Sons | location = Chichester | year = 2001 | isbn = 978-0-471-32642-7 }}
| |
| *{{Citation | last = Van Riper | first = A Bowdoin | title = Rockets and Missiles | publisher = Greenwood Press | location = Westport | year = 2004 | isbn = 978-0-313-32795-7 }}
| |
| *{{Citation |last1=von Braun |first1=Wernher |last2=Ordway |first2=Frederick Ira |title=History of rocketry & space travel |authorlink=Wernher Von Braun |year=1966 |publisher=Crowell |location=New York |oclc=566653}}
| |
| *{{Citation |last1=von Braun |first1=Wernher |editor= Emme, Eugene Morlock |title=The History of Rocket Technology: The Redstone, Jupiter and Juno |journal=Technology and Culture |volume=IV |issue=4 |date=Autumn 1963 |oclc=39186548 |pages=452–465 }}
| |
| *{{Citation | last = Zaloga | first = Steven | title = V-2 ballistic missile 1942-52 |series=New Vanguard |volume=82 | publisher = Oxford University Press | location = Oxford Oxfordshire | year = 2003 | isbn = 978-1-84176-541-9 }}
| |
| | |
| *{{Citation |url=http://history.msfc.nasa.gov/rocketry/tl1.html |title=Rockets in Ancient Times (100 B.C. to 17th Century) |accessdate=2009-06-28 |publisher=NASA |work=A Timeline of Rocket History |author=MSFC History Office}}
| |
| {{Refend}}
| |
| | |
| ==External links==
| |
| {{Wiktionary}}
| |
| {{Commons category|Rockets}}
| |
| ; Governing agencies
| |
| *[http://www.sderotmedia.com/ about the rocket in israel]
| |
| * [http://ast.faa.gov/ FAA Office of Commercial Space Transportation]
| |
| * [http://www.nasa.gov/ National Aeronautics and Space Administration (NASA)]
| |
| * [http://www.nar.org/ National Association of Rocketry (USA)]
| |
| * [http://www.tripoli.org/ Tripoli Rocketry Association]
| |
| * [http://www.acema.com.ar/ Asoc. Coheteria Experimental y Modelista de Argentina]
| |
| * [http://www.ukra.org.uk/ United Kingdom Rocketry Association]
| |
| * [http://www.modellraketen.org/ IMR - German/Austrian/Swiss Rocketry Association]
| |
| * [http://www.canadianrocketry.org/ Canadian Association of Rocketry]
| |
| * [http://www.isro.org/ Indian Space Research Organisation]
| |
| | |
| ; Information sites
| |
| * [[Encyclopedia Astronautica]] - [http://www.astronautix.com/lvs/ Rocket and Missile Alphabetical Index]
| |
| * [http://www.braeunig.us/space/index.htm Rocket and Space Technology]
| |
| * Gunter's Space Page - [http://space.skyrocket.de/ Complete Rocket and Missile Lists]
| |
| * [http://www.pwrengineering.com/data.htm Rocketdyne Technical Articles]
| |
| * [http://www.relativitycalculator.com/rocket_equations.shtml Relativity Calculator - Learn Tsiolkovsky's rocket equations]
| |
| * [http://sites.google.com/site/rgoddardsite Robert Goddard--America's Space Pioneer]
| |
| | |
| {{Aviation lists}}
| |
| {{Spaceflight}}
| |
| | |
| [[Category:Rocket-powered aircraft]]
| |
| [[Category:Rocketry]]
| |
| [[Category:Space launch vehicles]]
| |
| [[Category:Chinese inventions]]
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| [[Category:Gunpowder]]
| |