| Aerojet Rocketdyne|
1.6 m (62 in)
17.0 m (669 in)
46,697 kg (102,949 lb)
AJ-60A is a solid rocket booster produced by Aerojet Rocketdyne. They are currently used as strap-on boosters on United Launch Alliance's Atlas V rocket.
The AJ-60A rocket motor was developed between 1999 and 2003 for use on the Atlas V. In 2015, ULA announced that the Atlas V will switch to new GEM 63 boosters produced by Orbital ATK. A stretched version of this booster will be used on the upcoming Vulcan rocket.
AJ-60A is a solid fueled rocket burning HTPB. The casing is composed of a graphite epoxy composite, and the engine throat and nozzle are made of carbon-phenolic composite. As configured for use on Atlas V, the nozzle is fixed at a 3 degree cant away from the attachment point, but Aerojet offers a variant with thrust vectoring capability. The Atlas V configuration also features an inward slanting nosecone, but it is available with a conventional nosecone or none at all for use on other rockets. AJ-60A is the largest monolithic solid rocket motor currently in production. The stages are designed to be transported by truck.