Northrop Grumman conducted its second ground test of a 63-inch diameter Graphite Epoxy Motor (GEM 63) April 4 in Promontory, Utah.
The company developed this new side-mounted rocket motor to add power to the United Launch Alliance Atlas V launch vehicle.
The maximum thrust of the GEM 63 is 373,000 pounds or roughly the equivalent of five B-2 Spirit bombers. Up to five GEM 63 motors can support a single Atlas V launch.
“The Northrop Grumman team developed the GEM 63 motor in just three years, an impressive accomplishment for such a complex drop-in solution to an existing launch vehicle,” said Charlie Precourt, vice president, propulsion systems, Northrop Grumman.
The GEM 63 team developed the motor under a cooperative development program with ULA. Northrop Grumman has been supplying solid propulsion motors for a variety of launch vehicles since 1964 and is ULA’s largest legacy supplier of solid propulsion. Northrop Grumman’s expertise in solid rocket boosters combined with ULA’s history of reliability results in a strong partnership that guarantees assured access to space for national security.
“This test is an important step in the development of these new boosters for the Atlas V launch vehicle and we thank Northrop Grumman for the continued partnership and outstanding teamwork,” said Tory Bruno, ULA’s president and CEO. “By flying key hardware first on our Atlas V rocket prior to flying it on our Vulcan Centaur rocket, it provides increased confidence for the first flight of our new rocket in 2021.”
The first ground test, conducted in September 2018, qualified the motor for use as a strap-on booster for the Atlas V. Today’s test satisfies additional requirements for certification by the U.S. Air Force. The first launch using GEM 63 motors will take place in 2020.
In addition to the GEM 63 motor, Northrop Grumman is also developing a GEM 63XL motor for ULA’s Vulcan Centaur rocket. Both versions of the GEM 63 family use common materials and processes to maintain a high-reliability, low-cost product. The first GEM 63XL case, which is the longest non-segmented, monolithic case ever manufactured, has already been wound at a new facility in Clearfield, Utah, and is currently in the structural qualification process.