Kent Rominger. Credit: Moonandback media

WASHINGTON — Northrop Grumman says it can close the business case on its new OmegA launch vehicle with as few as four missions per year, owing in part to the company’s existing space and missile systems infrastructure, on which much OmegA development will draw.

One of four new vehicles competing for a national security space launch contract to be awarded by the U.S. Air Force next year, OmegA is designed to serve the civil and commercial communications satellite markets as well.

“We can go down to just two or three missions from the Air Force and our business case still closes, and that’s planning on only about two additional missions if times really get tight,” said Kent Rominger, vice president and capture lead for Northrop Grumman space launch systems. “Our plan is to fly more than that minimum of four missions, but we can go that low and our business case still closes.”

The Air Force awarded Northrop Grumman a $791 million launch services agreement in October 2018 to build and launch the first OmegA rockets starting in 2021. The company is now vying for the multi-year Air Force block buy that would see the service divvy up 34 launches between just two service providers over a five-year period starting in 2022.

Other rockets in the offing are the new Vulcan launch vehicle in development at incumbent United Launch Alliance (ULA), and the New Glenn vehicle offered by the Jeff Bezos-owned startup Blue Origin. SpaceX, whose Falcon Heavy lift rocket is certified for Air Force launches, is a fourth contender, though the company is not part of the service’s down-select.

Northrop Grumman has designed OmegA to comprise two rockets: an intermediate version able to lift about 85% of U.S. national security missions, as well as civil and commercial satellites; and a heavy variant for hard-to-reach, high-energy orbits. Both vehicles will incorporate Castor boost stages that draw on decades of solid-rocket-motor technology from NASA’s space shuttle program, as well as smaller motors that have flown on the Pentagon’s Minuteman and Trident missile systems.

“One of the ways that we have designed the system to be affordable is to leverage all that existing infrastructure; we need new tooling for OmegA, but we don’t have to put in much infrastructure,” Rominger said Oct 23 at the International Astronautical Congress (IAC) here. “Because our facilities that are manufacturing the solid rocket motors are not just doing OmegA, we can actually ebb and flow” between demand for national security launches and one or two commercial missions per year, Rominger said.

Credit: Northrop Grumman

Northrop Grumman test-fired the core stage Castor 600 in May. Although the test gathered a trove of data, an anomaly occurred, resulting in damage to the nozzle of the core stage solid-rocket-motor nozzle and pushing a static-fire test of the second-stage Castor 300 to the end of February next year, according to company officials.

Both the Castor 600 and Castor 300 will comprise the core stages of OmegA’s intermediate variant, which will be capable of lifting over 9,000 kg to geosynchronous transfer orbit. The heavy version, equipped with two Castor 600 boost stages, will be able to place 14,000 kg to GTO.

To augment core stage performance, both OmegA variants can fly up to six strap-on GEM-63XL boosters, which have flight heritage in ULA’s Delta 2 and Delta 4 programs. A similar booster, the GEM-63, is scheduled to fly on a ULA Atlas 5 rocket starting next year, following a successful third test-firing in October at Northrop Grumman’s Promontory, Utah, facility. It is slated to replace Aerojet Rocketdyne’s AJ-60A solid rocket booster.

For OmegA, Northrop is developing two variants of the GEM-63 motors: the baseline GEM-63XLT strap-on for enhanced performance, and a GEM-63XLT that is vectorable.

“For roll control we chose to use a vectorable nozzle rather than an existing attitude control system that’s on it for roll control without strap-ons,” Rominger said. “On the intermediate, you can choose zero to six strap-ons, but the first strap-on will always vector. After that they will be fixed.”

OmegA’s cryogenic third stage comprises Aerojet Rocketdyne’s flight-proven RL-10C engine, which currently powers the Centaur upper stage on ULA’s Atlas 5 and Delta 4 launchers.

“We designed this system to be simple to maintain a schedule for a tight timeline,” Rominger said of OmegA, which will fly two RL10Cs. “It has separate tanks for the liquid oxygen and the hydrogen. It’s going through qualifications, and it’s a very proven motor, so there’s minimal development on it.”

OmegA’s upper stage is currently being assembled at NASA’s Michoud Assembly Facility in New Orleans. Rominger said Northrop Grumman plans by the end of 2020 to have a completed stage in the vacuum chamber at NASA’s Plum Brook Station, near Cleveland, for testing.

OmegA will also incorporate avionics already in use on targets and interceptors designed for the U.S. missile defense system.

“We fly about 16 sets of those avionics per year on our smaller systems, on our targets, and that system has evolved for Omega as well,” Rominger said.

Like its competitor vehicles, OmegA is designed to serve the stringent requirements of national security missions, while simultaneously meeting an Air Force requirement to offer a commercially viable rocket.

However, unlike its competitors, OmegA is not designed to be reusable. Northrop Grumman has concluded that the economy of scale of a larger rocket requires putting as much energy into delivering a payload to orbit as possible, rather than reserving fuel to return the vehicle for reuse. It’s a frequent topic in the reusable-v-expendable debate.

Rominger said OmegA’s Castor motors will use a new electro-hydrostatic power unit for thrust-vector control.

“This size of motor in the past for NASA had a hydrazine-powered hydraulic power unit that gave you the hydraulics for the thrust-vector control, but we have transitioned to electro-hydrostatic by Moog,” Rominger said.

In addition, he said Northrop recently completed the winding of the first flight motor for the first Air Force certification flight slated for 2021.

OmegA also employs advances in solid rocket technology to ensure sensitive payloads have a smooth ride.

“We knew with these very expensive national security spaceflight satellites that could have very delicate instruments on board, you had to provide a great ride quality,” Rominger said. “We designed our motors for ride quality first, performance second. We were very careful in designing our system.”

The May 2019 static test firing of OmegA’s first stage. Credit: Northrop Grumman

With the ability to spread the cost of OmegA across existing production lines, and given the recent Castor 600 static fire test and an upcoming static fire of the Castor 300 expected at the end of February 2020, Northrop officials say the company is likely to continue the launch vehicle development in some form, even if it loses the Air Force tender.

In addition, Northrop Grumman has plans to augment OmegA’s liquid third stage to deliver missions beyond Earth’s orbit, potentially to cis-lunar space, Rominger said.

“With all the interest in trans-lunar now, we’re looking at NASA, who are looking for other spacecraft or launch vehicles to complement their Artemis program, and we know with the system today we can put 12.3 metric tons into trans-lunar orbit, and it’s similar for trans-martian orbits,” Rominger said. “Certainly on the heavy system we will evolve the upper stage to gain more performance to meet some of those demands that we see coming.”

In the meantime, Northrop Grumman is in the process of restructuring its development and production segments to combine space and launch capabilities under a new space systems division. During an Oct. 24 earnings call with analysts, Northrop Grumman CEO and President Kathy Warden said the realignment is a logical next step following the company’s acquisition of the former Orbital ATK in June 2018.

“We expect Space Systems will be the fastest growing sector in our new structure,” Warden said.