AJ10
The AJ10 is a hypergolic rocket engine manufactured by Aerojet Rocketdyne. It has been used to propel the upper stages of several launch vehicles, including the Delta II, Titan III and Orion MPCV. Variants were and are used as the service propulsion engine for the Apollo command and service module, in the Space Shuttle Orbital Maneuvering System, and on the European Service Module – part of NASA's Orion spacecraft.
Variants
Many AJ10 engine variations were developed over the years, summarized on the following table:| Model | Propellant | Used on | First flight | Notes | |
| AJ10 | / UDMH | Vanguard | |||
| AJ1011B | / UDMH | ||||
| AJ1021 | / Aniline | Aerobee RV-N-13b | |||
| AJ1024 | / Aniline | Aerobee RTV-N-10b | |||
| AJ1025 | / Aniline | Aerobee RTV-A-1a, RTV-A-1c, RTV-N-10a, Aerobee AJ10-25 | |||
| AJ1027 | / Aniline | Aerobee AJ10-27 | |||
| AJ1034 | / Aniline | Aerobee RTV-N-10c, Aerobee AJ10-34 | |||
| AJ1037 | / UDMH | Vanguard | 1958 | Vanguard second stage | |
| AJ1040 | / UDMH | Thor-Able | 1958 | Able stage | |
| AJ1041 | / UDMH | Thor-Able I | 1958 | Able stage | |
| AJ1042 | / UDMH | Thor-Able II | 1959 | Able stage | |
| AJ10101 | / UDMH | Atlas-Able, Thor-Able | 1958 | ABLE-1 lunar probes | |
| AJ10101A | / UDMH | Atlas-Able IV, V; Thor-Able III, IV | 1959 | ||
| AJ10104 | / UDMH | Thor-Ablestar | 1960 | Ablestar | |
| AJ10104D | / UDMH | Thor-Ablestar | 1963 | Ablestar | |
| AJ10118 | / UDMH | Delta A, Thor/ASSET | 1960 | Long Tank Able stage for Delta | |
| AJ10118A | / UDMH | Delta B | |||
| AJ10118D | / UDMH | Delta B, C, D | 1962 | ||
| AJ10118E | / UDMH | Delta E, G, J, L, M, N | 1965 | ||
| AJ10118F | / UDMH | Delta 0100, 1000 | 1972 | Transtage derived | |
| AJ10118G | / UDMH | Delta G | 1965 | ||
| AJ10118H | / UDMH | Delta H | |||
| AJ10118FJ | / UDMH | N-II | 1981 | Transtage derived | |
| AJ10118K | / Aerozine-50 | Delta 4000, 5000, II | 1982 | Pressure-fed, altitude-optimized | |
| AJ10131 | / Aerozine-50 | Subscale Apollo Service Propulsion System | |||
| AJ10137 | / Aerozine-50 | Apollo Service Module | Pressure-fed | ||
| AJ10138 | / Aerozine-50 | Titan IIIC, Titan IIIA, Titan 34D, Titan 3C7 | 1964 | Originally developed for Vanguard and Able, flown as Transtage | |
| AJ10138A | / Aerozine-50 | Titan IIIC, Titan IIIA, Titan 34D, Titan 3C7 | Transtage | ||
| AJ10190 | / | Shuttle OMS, European Service Module | 1981 | Also called the Orbital Maneuvering Engine. Refurbished shuttle engines used on ESM. Only reusable variant in the AJ10 family. | |
| AJ10198 | Kick stage engine | ||||
| AJ10196 | Liquid throttling engine. | ||||
| Transtar | / | Transtar | Pump-fed upper stage engine based on Shuttle OMS components. |
AJ10-37
The AJ10 engine was first used in the Delta-A/Able second stage of the Vanguard rocket, in the AJ10-37 configuration. It was initially fueled by and UDMH. An AJ10 engine was first fired in flight during the third Vanguard launch, on 17 March 1958, which successfully placed the Vanguard 1 satellite into orbit.AJ10-101
The AJ10-101 engine was used on an uprated version of the Able stage, used on Atlas-Able and Thor-Able rockets. The first AJ10-101 flight, with a Thor-Able, occurred on 23 April 1958; however, the Thor failed before the upper Able stage fired. The second flight, which saw the first in flight firing of an AJ10-101 engine, occurred on 10 July 1958.AJ10-138
The AJ10-138 engine was originally developed for Vanguard and Able, and was flown from 1964 to 1980.Two of these engines were used in the Titan III GTO Transtage, with thrust uprated from to, and with a higher specific impulse of.
AJ10-137
The AJ10-137 engine was used in the Apollo service module's service propulsion system from first flight in 1966. Trans-Earth injection, from lunar orbit, was the most critical usage of this engine during the Apollo program.This version used Aerozine 50 as fuel and nitrogen tetroxide as oxidizer, rather than the previous nitric acid/UDMH.
AJ10-118F
The AJ10-118F engine produced of thrust and was derived from the AJ10-138 engine used on the Transtage. It was used by the Delta-F upper stage of the Delta 1000 Straight Eight series rocket, starting in 1972.This version also used Aerozine 50 as fuel and nitrogen tetroxide as oxidizer.
AJ10-190
The AJ10-190 engine was used on the Space Shuttle Orbital Maneuvering System for orbital insertion, on-orbit maneuvers, and de-orbiting, first flown in 1981. They produced of thrust with a specific impulse of 316 seconds.Following the retirement of the Shuttle, these engines were repurposed for use on the Orion spacecraft's service module. This variant uses as fuel, with nitrogen tetroxide as oxidizer.