The GE X-405 — U.S. Navy designation XLR50-GE-2 — was a pump-fed

liquid-propellant rocket A liquid-propellant rocket or liquid rocket utilizes a rocket engine that uses liquid rocket propellant, liquid propellants. Liquids are desirable because they have a reasonably high density and high Specific impulse, specific impulse (''I''sp). T ...

engine burning RP-1 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 applica ...

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 energ ...

. 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 developed ...

experience, the turbine was driven by steam generated by catalytic decomposition of H₂O₂ and the combustion chamber was regeneratively cooled. The engine was

gimbaled A gimbal is a pivoted support that permits rotation of an object about an axis. A set of three gimbals, one mounted on the other with orthogonal pivot axes, may be used to allow an object mounted on the innermost gimbal to remain independent of ...

to supply thrust vectoring. 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 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 propulsion (the Reaction Motors

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, 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