The GE X-405 —

U.S. Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage o ...

designation XLR50-GE-2 — was a pump-fed liquid-propellant rocket engine burning

RP-1 RP-1 (alternatively, Rocket Propellant-1 or Refined Petroleum-1) is a highly refined form of kerosene outwardly similar to jet fuel, used as rocket fuel. RP-1 provides a lower specific impulse than liquid hydrogen (LH2), but is cheaper, is s ...

and

LOX Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an appli ...

in a

gas generator A gas generator is a device for generating gas. A gas generator may create gas by a chemical reaction or from a solid or liquid source, when storing a pressurized gas is undesirable or impractical. The term often refers to a device that uses a ...

cycle developed by

General Electric General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable en ...

. It was used to power the first stage of the Vanguard rockets on the Vanguard project. As was common to engines based on the

V-2 The V-2 (german: Vergeltungswaffe 2, lit=Retaliation Weapon 2), with the technical name ''Aggregat 4'' (A-4), was the world’s first long-range guided ballistic missile. The missile, powered by a liquid-propellant rocket engine, was develope ...

experience, the turbine was driven by steam generated by

catalytic Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...

decomposition of H₂O₂ and the combustion chamber was regeneratively cooled. The engine was gimbaled to supply

thrust vectoring Thrust vectoring, also known as thrust vector control (TVC), is the ability of an aircraft, rocket, or other vehicle to manipulate the direction of the thrust from its engine(s) or motor(s) to control the attitude or angular velocity of the ve ...

. Also, the exhaust gases of the turbine were ducted to dual auxiliary nozzles that acted as verniers to enable roll control of the rocket. When the

Vanguard The vanguard (also called the advance guard) is the leading part of an advancing military formation. It has a number of functions, including seeking out the enemy and securing ground in advance of the main force. History The vanguard derives fr ...

rocket was selected as the first orbital launch vehicle for the US, Martin Company got the contract as prime contractor. Given the required thrust levels, the

Viking Vikings ; non, víkingr is the modern name given to seafaring people originally from Scandinavia (present-day Denmark, Norway and Sweden), who from the late 8th to the late 11th centuries raided, pirated, traded and se ...

propulsion (the

Reaction Motors Reaction Motors, Inc. (RMI) was an early American maker of liquid-fueled rocket engines, located in New Jersey. RMI engines with thrust powered the Bell X-1 rocket aircraft that first broke the sound barrier in 1947, and later aircraft such ...

XLR10 Viking was series of twelve sounding rockets designed and built by the Glenn L. Martin Company under the direction of the U.S. Naval Research Laboratory (NRL). Designed to supersede the German V-2, the Viking was the most advanced large, liqu ...

) was deemed insufficient, and instead, the

proposal, based on the experience gained in the

Hermes program Project Hermes was a missile research program run by the Ordnance Corps of the United States Army from November 15, 1944, to December 31, 1954, in response to Germany's rocket attacks in Europe during World War II. The program was to determine ...

, was considered more fitting and a less risky choice than Reaction Motors next project. Thus, on October 1, 1955 Martin purchase order 55-3516-CP was signed with General Electric for the X-405 engine for furnishing a self-contained unit which was to include the thrust structure, gimbal ring, engine components, and engine starting equipment. While the first two Vanguard flight, ( TV-0 and TV-1), used Viking first stages, twelve X-405 were built and eleven flew on Vanguard rockets.

References

Further reading