AJ-60A

AJ-60A is a solid rocket booster produced by Aerojet Rocketdyne. Up to 2020 they were used as strap-on boosters on all United Launch Alliance Atlas V rocket configurations. They continue to be used on the Atlas V N22 configuration used to launch the Boeing Starliner.^[1]

AJ-60A

An AJ-60A booster, without nosecone attached, being fitted to an Atlas V
Manufacturer	Aerojet Rocketdyne
Country of origin	USA
Used on	Atlas V
General characteristics
Height	17.0 m (669 in)
Diameter	1.6 m (62 in)
Gross mass	46,697 kg (102,949 lb)
Engine details
Maximum thrust	1,688.4 kN (379,600 lbf)
Burn time	94 seconds
Propellant	HTPB/AP (APCP)

History

The AJ-60A rocket motor was developed between 1999 and 2003 for use on the Atlas V.^[2]

On January 19, 2006 the New Horizons spacecraft to Pluto was launched directly into a solar-escape trajectory at 16.26 kilometers per second (58,536 km/h; 36,373 mph) from Cape Canaveral using an Atlas V version with 5 of these SRBs and Star 48B third stage.^[3] New Horizons passed the Moon's orbit in just nine hours.^[4][5]

In 2015, ULA announced that the Atlas V will switch to new GEM 63 boosters produced by Northrop Grumman Innovation Systems. (GEM 63XL, a stretched version of the GEM 63 booster is used on the Vulcan rocket.)^[6] The first Atlas V launched with GEM 63 boosters on November 13, 2020.^[7]

Design

AJ-60A is a solid fueled rocket burning HTPB-based composite solid propellant.^[8] 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.^[2] 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. The stages are designed to be transported by truck.^[8]

References

1. Clark, Stephen (May 15, 2021). "Billion-dollar missile defense satellite ready for launch Monday in Florida". Spaceflight Now. Retrieved August 8, 2024.
2. "Atlas V Solid Rocket Booster". Archived from the original on March 14, 2017. Retrieved January 6, 2016.
3. Scharf, Caleb A. (February 25, 2013). "The Fastest Spacecraft Ever?". Scientific American. Retrieved July 12, 2017.
4. Neufeld, Michael (July 10, 2015). "First Mission to Pluto: The Difficult Birth of New Horizons". Smithsonian. Retrieved April 21, 2018.
5. "New Horizons: Mission Overview" (PDF). International Launch Services. January 2006. Archived from the original (PDF) on September 9, 2016. Retrieved April 21, 2018.
6. Jason Rhian (23 September 2015). "ULA selects Orbital ATK's GEM 63/63 XL SRBs for Atlas V and Vulcan boosters". Spaceflight Insider. Archived from the original on 11 January 2016. Retrieved 6 January 2016.
7. Northrop Grumman Ships GEM 63 Engines to United Launch Alliance For Atlas V July 2020
8. "Atlas V User's Guide 2010" (PDF). 2010. Archived from the original (PDF) on March 6, 2012. Retrieved January 6, 2016.