In addition to launching science and commercial payloads, the OmegA space launch vehicle – one of Northrop Grumman’s largest strategic investments – is designed launch the full range of national security missions required by the U.S. Air Force (USAF) under the Evolved Expendable Launch Vehicle (EELV) program.
This cast of a C600 rocket motor required a record 55 mixes of propellant that are 600-gallons each. The mixture is derived from NASA Space Shuttle booster fuel. (Image source: Northrop Grumman)
The USAF began the EELV program in the 1990s to secure affordable and reliable space access for U.S. Department of Defense payloads. The Atlas V, Delta IV, and recently SpaceX’s Falcon 9 also serve through the EELV program.
The casting of the aft motor segment, the CASTOR 600 (C600), follows the completion of an inert cast in April, which marked the largest solid rocket motor casting campaign in Northrop Grumman history. It will have a capacity to deliver up to 10,100 kilograms of payload to geostationary transfer orbit (GTO) and up to 7,800 kilograms to geostationary equatorial orbit (GEO). The C600 aft segment is the heaviest of any of the CBS motor segments, requiring a record fill of 33,000 gallons of propellant.
For comparison, the second-heaviest Promontory-cast rocket motor segment is a NASA Space Launch System (SLS) booster forward segment requiring 27,000 gallons of propellant. The initial inert cast enabled the Northrop Grumman team to uncover any potential process issues before live casting.
The C600 aft segment is the heaviest of any of the CBS motor segments. (Image source: Northrop Grumman)
The OmegA launch vehicle will use three stages and strap-on boosters to launch payloads into space, as shown in this diagram. (Image source: Northrop Grumman)
“Our team succeeded beautifully in meeting this important milestone for our OmegA rocket,” says Charlie Precourt, vice president and general manager of propulsion systems at Northrop Grumman. “We have two more live motor casts, and we will be ready for ground tests next year.”
To reduce development time and leverage pre-existing infrastructure, the OmegA shares common propulsion, architecture, and avionics systems with current and future Northrop Grumman programs. The company claims that commonality between other Northrop Grumman and USAF launch vehicles should provide a cost savings of approximately $600 million in government spending on similarly configured rockets over the course of 10 years.
On average, Northrop Grumman builds 20 rockets and launches 14 each year, and has designed and built a new rocket every two years for the past decade. Over the last three years the company has been on schedule and within budget while progressing on the CBS design and initial test and verification hardware.
The first static test for the program is a C600, consisting of a forward and an aft segment mated together, and the second is a C300, which is a single segment motor. Both tests are planned for 2019 and will verify the first and second stage performance for OmegA’s intermediate vehicle configuration, which will make up the majority of the anticipated flights beginning in 2021. Aerojet Rocketdyne of Sacramento, Calif. Will supply a RL10C engine for the vehicle’s upper stage propulsion system.
Like other EELVs, OmegA will operate from both east and west coast launch facilities.
The OmegA program was initially started by Orbital ATK Inc., which formed in 2015 from a merger between Dulles, Va.-based Orbital Sciences Corporation and components of Arlington County, Va.-based Alliant Techsystems. Orbital ATK was purchased by Northrop Grumman in 2018 and reformed as Northrop Grumman Innovation Systems. Northrop Grumman Innovation Systems continues to design, build, and deliver space and defense systems from its division headquarters in Dulles.
William Kucinski is content editor at SAE International, Aerospace Products Group in Warrendale, Pa. Previously, he worked as a writer at the NASA Safety Center in Cleveland, Ohio and was responsible for writing the agency’s System Failure Case Studies. His interests include 'literally anything that has to do with space,' past and present military aircraft, and propulsion technology. And also sportscars.
Contact him regarding any article or collaboration ideas by e-mail at firstname.lastname@example.org.
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