A rocket-powered aircraft or rocket plane is an aircraft that uses a rocket engine for propulsion, sometimes in addition to airbreathing jet engines. Rocket planes can achieve much higher speeds than similarly sized jet aircraft, but typically for at most a few minutes of powered operation, followed by a gliding flight. Unhindered by the need for oxygen from the atmosphere, they are suitable for very high-altitude flight. They are also capable of delivering much higher acceleration and shorter takeoffs. Many rocket aircraft may be drop launched from transport planes, as take-off from ground may leave them with insufficient time to reach high altitudes.
Rockets have been used simply to assist the main propulsion in the form of jet assisted take off (JATO) also known as rocket-assisted takeoff (RATO or RATOG). Not all rocket planes take off in the conventional manner for planes. Some types have been air-launched from another plane, while other types have taken off vertically – nose in the air and tail to the ground ("tail-sitters").
Because of the use of heavy propellants and other practical difficulties of operating rockets, the majority of rocket planes have been built for experimental or research use, as interceptor fighters and space aircraft.
History Background
Peruvian polymath Pedro Paulet conceptualized the Avión Torpedo in 1902 – a liquid-propellant rocket-powered aircraft that featured a canopy fixed to a delta tiltwing – spending decades seeking donors for the aircraft while serving as a diplomat in Europe and Latin America. Paulet's concept of using liquid-propellant was decades ahead of rocket engineers at the time who utilized black powder as a propellant. Reports of Paulet's rocket aircraft concept first appeared in 1927 after Charles Lindbergh crossed the Atlantic Ocean in an aircraft. Paulet publicly criticized Austrian rocket pioneer Max Valier's proposal about a rocket-powered aircraft completing the journey faster using black powder, arguing that his liquid-propellant rocket aircraft from thirty years earlier would be a better option.
Paulet would go on to visit the German rocket association Verein für Raumschiffahrt (VfR) and on March 15, 1928, Valier applauded Paulet's liquid-propelled rocket design in the VfR publication Die Rakete, saying the engine had "amazing power". In May 1928, Paulet was present to observe the demonstration of a rocket car of the Opel RAK program of Fritz von Opel and Max Valier, and after meeting with the German rocket enthusiasts. VfR members began to view black powder as a hindrance for rocket propulsion, with Valier himself believing that Paulet's engine was necessary for future rocket development. Paulet would soon be approached by Nazi Germany to help develop rocket technology, though he refused to assist and never shared the formula for his propellant. The Nazi government would then appropriate Paulet's work while a Soviet spy in the VfR, Alexander Boris Scherchevsky, possibly shared plans with the Soviet Union.
On 11 June 1928, as part of the Opel RAK program of Fritz von Opel and Max Valier, Lippisch Ente became the first aircraft to fly under rocket power.https://www.airforcemag.com/article/0904rocket/ article by Walter J. Boyne in Air Force Magazine, September 1, 2004"Lippisch Ente." The Internet Encyclopedia of Science: Experimental Aircraft. Retrieved: 26 September 2011.Ford 2013, p. 224. During the following year, the Opel RAK.1 became the first purpose-built rocket plane to fly with Fritz von Opel himself as the pilot. The Opel RAK.1 flight is also considered the world's first public flight of a manned rocket plane since it took place before a large crowd and with world media in attendance.
On 28 June 1931, another ground-breaking rocket flight was conducted by the Italian aviator and inventor Ettore Cattaneo, who created another privately built rocket plane. It flew and landed without particular problems. Following this flight, the King of Italy Victor Emmanuel III appointed Cattaneo count of Taliedo; due to his pioneering role in rocket flight, his likeness is displayed in the Space Museum of Saint Petersburg as well as in the Museum of Science and Tech of Milan.
World War II The Heinkel He 176 was the world's first aircraft to be propelled solely by a liquid-propellant rocket engine. It performed its first powered flight on 20 June 1939 with Erich Warsitz at the controls.Warsitz, Lutz. The First Jet Pilot: The Story of German Test Pilot Erich Warsitz. London: Pen and Sword Books Ltd., 2009. . The He 176, while demonstrated to the Reich Air Ministry did not attract much official support, leading to Heinkel abandoning its rocket propulsion endeavours; the sole aircraft was briefly displayed at the Berlin Air Museum and was destroyed by an Allied bombing raid in 1943.Tuttle, Jim. Eject! The Complete History of U.S. Aircraft Escape Systems. St. Paul, Minnesota: MBI Publishing Company, 2002. .
The first rocket plane ever to be mass-produced was the Messerschmitt Me 163 Komet interceptor, introduced by Germany towards the final years of the conflict as one of several efforts to develop effective rocket-powered aircraft. plane-crazy.net. Retrieved: 26 September 2011. The Luftwaffe's first dedicated Me 163 fighter wing, Jagdgeschwader 400 (JG 400) was established in 1944, and was principally tasked with providing additional protection for the manufacturing plants producing synthetic gasoline, which were prominent targets for Allied air raids. It was planned to station further defensive units of rocket fighters around Berlin, the Ruhr and the German Bight.Galland 1957, p. 251.
A typical Me 163 tactic was to fly vertically upward through the bombers at , climb to , then dive through the formation again, firing as they went. This approach afforded the pilot two brief chances to fire a few rounds from his cannons before gliding back to his airfield. It was often difficult to supply the needed fuel for operating the rocket motors. In the final days of the Third Reich, the Me 163 was withdrawn in favor of the more successful Messerschmitt Me 262, which used jet propulsion instead.Späte 1989, p. 252.
Other German rocket-powered aircraft were pursued as well, including the Bachem Ba 349 "Natter", a vertical takeoff manned rocket interceptor aircraft that flew in prototype form.Lommel 1998, p. 92.Bachem 1952, pp. 89–96. Further projects never reached the prototype stage, such as the Zeppelin Rammer, the Fliegende Panzerfaust and the Focke-Wulf Volksjäger. Having a much larger size than any other rocket-powered endeavor of the conflict, the Silbervogel antipodal bomber spaceplane was planned by the Germans, however, later calculations showed that design would not have worked, instead being destroyed during reentry.Parsons, Zach. My Tank is Fight. London: Citadel, 2006. . The Me 163 Komet is the only type of rocket-powered fighter to see combat in history, and one of only two types of rocket-powered aircraft seeing any combat.
Japan, who was allied to Nazi Germany, secured the design schematics of the Me 163 Komet. After considerable effort, it successfully established its own production capability, which was used to produce a limited number of its own copies, known as the Mitsubishi J8M, which performed its first powered flight on 7 July 1945. Furthermore, Japan attempted to develop its own domestically designed rocket-powered interceptor, the Mizuno Shinryu; neither the J8M or the Shinryu ever saw combat.Dyer 2009, pp. 40–42. The Japanese also produced approximately 850 Yokosuka MXY-7 Ohka rocket-powered suicide attack aircraft during the Second World War, a number were deployed in the Battle of Okinawa. Postwar analysis concluded that the Ohkas impact was negligible, and that no U.S. Navy capital ships had been hit during the attacks due to the effective defensive tactics that were employed.Kightly, James. "Yokosuka Ohka Kamikaze Pilot." Aeroplane, Volume 39, No. 7, Issue no. 459, July 2011, pp. 30–31.
Other experimental aircraft included the Soviet Bereznyak-Isayev BI-1 that flew in 1942 while the Northrop XP-79 was originally planned with rocket engines but switched to jet engines for its first and only flight in 1945. A rocket-assisted P-51D Mustang was developed by North American Aviation that could attain .Santiago – The Rocket-Boosted P-51 Mustang – Tuesday, December 28, 2010 The engine ran on red fuming nitric acid and aniline which was stored in two under wing drop tanks. The plane was tested in flight in April 1945. The rocket engine could run for about a minute. Similarly, the Messerschmitt Me 262 "Heimatschützer" series used a combination of rocket and jet propulsion to allow for shorter take-offs, faster climb rate, and even greater speeds.Reddin, Shamus http://www.walterwerke.co.uk/ato/me262i.htm Me.262 Heimatschützer I. The Walter 109-509.S1 Assisted Take-Off Unit. "The Hellmuth Walter Rocket Motor Web Site" Retrieved: 2 February 2022
Cold War era
During 1946, the Soviet Mikoyan-Gurevich I-270 was constructed in response to a Soviet Air Forces requirement issued during the previous year for a rocket-powered interceptor aircraft in the point-defence role. The design of the I-270 incorporated several pieces of technology that had been developed by Sergei Korolev between 1932 and 1943.Bille and Lishock 2004, p. 9.
During 1947, a key milestone in aviation history was reached by the rocket-powered Bell X-1, which became the first aircraft to break the speed of sound in level flight, and would be the first of a series of NACA/NASA rocket-powered aircraft."Bell X-1." allstar.fiu.edu. Retrieved: 26 September 2011. Amongst these experimental aircraft were the North American X-15 and X-15A2 designs, which were operated for around a decade and eventually attained a maximum speed of Mach 6.7 as well as a peak altitude in excess of 100 km, setting new records in the process."North American X-15 High-Speed Research Aircraft." Aerospaceweb.org, 24 November 2008.
During the 1950s, the British developed several mixed power designs to cover the performance gap that existed in then-current turbojet designs. The rocket was the main engine for delivering the speed and height required for high speed interception of high level bombers and the turbojet gave increased fuel economy in other parts of flight, most notably to ensure that the aircraft was able to make a powered landing rather than risking an unpredictable gliding return.Jones Aeroplane Monthly November 1994, pp. 32–33.Wood 1975, p. 55. One design was the Avro 720, which was primarily propelled by an 8,000 lbf (36 kN) Armstrong Siddeley Screamer rocket engine that ran on kerosene fuel mixed with liquid oxygen as the oxidizing agent.Mason 1992, p. 400. Work on the Avro 720 was abandoned shortly after the Air Ministry's decision to terminate development of the Screamer rocket engine, allegedly due to official concerns regarding the practicality of using liquid oxygen, which boils at -183 °C (90 K) and is a fire hazard, within an operational environment.London 2010, p. 30.Flight 24 May 1957, pp. 698–699.Wood 1975, p. 61.