Reaction Motors
Reaction Motors was an early American rocket-engine manufacturer whose liquid-fueled engines powered major experimental aircraft and high-altitude rocket programs.
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Overview
Reaction Motors, Inc. was an early American aerospace propulsion company based in New Jersey. It developed liquid-fueled rocket engines for military missiles, experimental aircraft, research rockets, and later crewed-flight technology. The company is particularly associated with the Bell X-1, the aircraft in which Chuck Yeager broke the sound barrier in 1947, and with the XLR-99 engine that powered the North American X-15 during the United States’ early high-speed and high-altitude flight research. The company grew out of experimental rocketry conducted by members of the American Interplanetary Society, later known as the American Rocket Society. Lovell Lawrence, George Edward Pendray, Hugh Pierce, John Shesta, and engineer James Hart Wyld were among the figures involved in moving the group’s interests from theoretical discussion toward practical engine development. A major early technical achievement was the development of a workable regenerative-cooling approach for liquid-fueled rocket engines. By circulating propellant through cooling passages around the combustion chamber, this method helped engines operate for useful durations without destroying their chambers. The principle became fundamental to later liquid-rocket propulsion. Reaction Motors was incorporated in December 1941 and became the first commercial rocket-engine company in the United States. Its early operations were modest, beginning with limited facilities and a small start-up budget before expanding into premises in New Jersey suitable for machining and engine testing. The company received a United States Navy contract in 1942 and later undertook Army work connected with the experimental aircraft program that produced the Bell X-1. For the X-1, Reaction Motors supplied four engines based on Wyld’s designs. Together they produced approximately 6,000 pounds-force of thrust. On October 14, 1947, Chuck Yeager used the powered X-1 to become the first person to fly faster than sound in level flight. Reaction Motors engines also supported later X-1 variants and the Douglas D-558-2 Skyrocket, extending the company’s role in American supersonic-flight research. The company’s work expanded into larger propulsion systems. Its XLR10 engine powered the Viking research rocket, described in the reference material as the first large American liquid-fueled high-altitude rocket. Reaction Motors also produced engines for missiles including the Lark, Gorgon, Hiroc, and AGM-12 Bullpup. In the late 1950s it became involved in the X-15 program, initially developing the XLR30 concept and eventually producing the substantially revised XLR-99 engine. The XLR-99 first flew in 1960 and powered the X-15 through 199 flights before the program ended in 1969. The aircraft reached Mach 6.72 and generated data used in the development of later high-speed aircraft and spacecraft. Thiokol Chemical Corporation acquired Reaction Motors in 1958, after which the business operated as the Reaction Motors Division. Under Thiokol, the division also worked on propulsion for the Surveyor lunar probes and other aerospace and missile systems. Thiokol disbanded the division in 1972. Reaction Motors therefore survives primarily as a historical aerospace-propulsion name rather than as an active independent brand.
History
Reaction Motors emerged from the prewar American rocketry movement. Its early contributors were associated with the American Interplanetary Society, an organization that encouraged practical experimentation as well as public discussion of spaceflight. Lovell Lawrence, George Edward Pendray, Hugh Pierce, John Shesta, and James Hart Wyld helped establish the technical and organizational foundation for the company. Pendray brought additional knowledge from European rocketry activities, while Wyld’s small experimental engine work provided a basis for later designs. The group conducted rocket tests during the 1930s and incorporated Reaction Motors, Inc. in 1938 under Lawrence’s leadership. Before incorporation, it had developed a practical regenerative-cooling system for liquid-fueled rocket engines. This innovation allowed propellant to cool the combustion chamber and made longer-duration liquid-fueled operation more feasible. The company initially operated with very limited resources, using a small New Jersey workshop and later moving to facilities that could accommodate machining and propulsion tests. In 1941 it was formally incorporated, becoming the first commercial rocket-engine company in the United States according to the cited historical account. Reaction Motors received a Navy contract in 1942 and entered a period of closer involvement with government aerospace and missile programs. In 1945 the United States Army contracted the company to develop propulsion for an experimental aircraft in the X-series. The resulting XLR11-based installation for the Bell X-1 used four engines, each producing approximately 1,500 pounds-force of thrust. On October 14, 1947, Chuck Yeager piloted the X-1 through the first successful supersonic flight. Reaction Motors propulsion was subsequently used on the X-1A, X-1E, and Douglas D-558-2 Skyrocket. The company also developed larger engines. Its XLR10 powered the Viking research rocket, a major American high-altitude research vehicle. Other engines were supplied for missile projects, including the Lark, Gorgon, Hiroc, and Bullpup systems. These projects demonstrate that Reaction Motors operated across both experimental aviation and defense propulsion rather than focusing on a single aircraft product. In the mid-1950s, Reaction Motors won a Navy competition to develop propulsion for the proposed X-15 research aircraft. The initial XLR30 effort encountered significant technical difficulties, including problems involving fuel injection and the thrust chamber. Assistance from Rocketdyne, a division of North American Aviation, contributed to a major redesign. The resulting engine received the designation XLR-99-RM-1. Thiokol’s acquisition of Reaction Motors was approved in April 1958, and the company thereafter operated as the Reaction Motors Division. The XLR-99 first flew in November 1960 and powered the X-15 for 199 flights before the program ended in 1969. The aircraft achieved a reported maximum speed of Mach 6.72 and reached an altitude of approximately 67 miles. Data from the program supported advances in high-speed aerodynamics, thermal protection, flight control, and spacecraft design, including work relevant to the Mercury spacecraft. During the Thiokol period, the division also developed propulsion for the AGM-12 Bullpup missile and vernier engines for Surveyor probes. Thiokol disbanded the division in 1972, leaving Reaction Motors as a historical name associated with the formative era of American rocket propulsion.
- 1972
Division disbanded
[1]Thiokol disbanded the Reaction Motors Division.
- 1969
End of the X-15 program
[1]The X-15 program ended after 199 flights powered by the XLR-99, following a record-setting research campaign.
- 1960
First flight of the XLR-99
[1]The substantially revised XLR-99 engine first flew on the X-15 in November.
- 1958
Acquisition by Thiokol
[1]Thiokol Chemical Corporation completed the acquisition, and Reaction Motors became the Reaction Motors Division.
- 1956
X-15 engine contract
[1]Reaction Motors won a Navy competition to develop the propulsion system for the experimental X-15 aircraft.
- 1947
Bell X-1 breaks the sound barrier
[1]Chuck Yeager flew the Bell X-1 beyond the speed of sound using four Reaction Motors engines.
- 1945
Army X-aircraft propulsion contract
[1]The company received an Army contract to develop an engine for the experimental X-aircraft program that led to the Bell X-1.
- 1942
First cited Navy contract
[1]Reaction Motors received its first United States Navy contract, helping establish its government-propulsion business.
- 1941
Formal incorporation and commercial operation
[1]The company was incorporated in December 1941 and became an early commercial American rocket-engine manufacturer.
- 1938
Reaction Motors is incorporated
[1]Reaction Motors, Inc. was incorporated in New Jersey under Lovell Lawrence as the rocketry group moved toward commercial and government-sponsored engine development.
Products and positioning
A pioneering American developer of liquid-fueled rocket propulsion for experimental flight, military systems, and early space research.
Experimental-aircraft rocket engine
XLR11
The XLR11 was a small liquid-fueled rocket engine used in several American research and experimental aircraft. Reaction Motors installations powered the Bell X-1 and later X-1 variants, as well as the Douglas D-558-2 Skyrocket and early X-15 configurations. Its use across multiple high-speed aircraft made it one of the company’s most historically visible propulsion products.
Research-rocket engine
XLR10
The XLR10 was a larger liquid-fueled engine associated with the Viking research rocket program. Viking was developed for high-altitude research and represented an important step in American liquid-rocket development before the maturation of larger launch vehicles.
Research-aircraft rocket engine · 1960
XLR-99-RM-1
The XLR-99 was the principal Reaction Motors Division engine for the North American X-15. It followed extensive redesign of the earlier XLR30 concept after injector, thrust-chamber, and related engineering difficulties. The engine first flew in 1960 and powered the X-15’s high-speed research missions through the program’s conclusion.
Missile engine
LR58-RM-4
The LR58-RM-4 was a Reaction Motors liquid-fueled engine used in the AGM-12 Bullpup missile family, extending the company’s work from research aircraft into guided-weapon propulsion.
Surface-to-air missile engines
LR2-RM-2 and LR2-RM-6
These engines were used in the SAM-N-2 Lark missile program. They formed part of Reaction Motors’ early portfolio of propulsion systems for American military missiles.
Missile engine
CML2N
The CML2N was listed among Reaction Motors engines used on the Gorgon IIA and Gorgon III missile systems.
Missile engine
XLR35-RM-1
The XLR35-RM-1 was associated with the RTV-A-2 Hiroc missile program.
Spacecraft auxiliary propulsion
Surveyor vernier engines
During its Thiokol-era operation, Reaction Motors Division developed vernier engines for Surveyor probes. These small propulsion units supported spacecraft attitude and trajectory-control functions in the early American lunar exploration program.
Brand decisions
1958
Join Thiokol as Reaction Motors DivisionM&ABackground
Reaction Motors had expanded from an early independent rocket-engine company into a supplier for major military and experimental-flight programs, including the developing X-15 engine.
Action taken
Thiokol Chemical Corporation acquired Reaction Motors after stockholder approval in April 1958, converting the company into the Reaction Motors Division.
Aftermath
The division continued propulsion development under Thiokol, including the XLR-99 for the X-15 and engines for missiles and Surveyor spacecraft, until Thiokol disbanded it in 1972.
1956
Develop the X-15 propulsion systemProduct launchBackground
The United States Navy sought a high-performance liquid-fueled engine for the X-15 experimental aircraft and awarded the development contract after a competitive process.
Action taken
Reaction Motors began work on the XLR30 engine concept, which was later extensively redesigned and redesignated XLR-99-RM-1.
Aftermath
The XLR-99 entered flight testing in 1960 and powered the X-15 through 199 flights.
Recent events
- 1972
Reaction Motors Division is disbanded[1]
Other
Thiokol ended the Reaction Motors Division, bringing the independent operating history of the company’s brand to a close.
- 1960
XLR-99 engine flies on the X-15[1]
Product launch · Product generation
The XLR-99, developed by Reaction Motors Division for the North American X-15, made its first flight and became the aircraft’s principal propulsion system.
- 1958
Thiokol acquisition creates Reaction Motors Division[1]
M&A
Thiokol Chemical Corporation completed its acquisition of Reaction Motors, after which the company operated as a Thiokol division.
- 1947
Reaction Motors engines power the Bell X-1 supersonic flight[1]
Other
The Bell X-1, powered by four Reaction Motors engines, carried Chuck Yeager on the flight that first exceeded the speed of sound.
Sources2 sources
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