Space Exploration Technologies Corp. (SpaceX) CEO and Chief Designer Elon Musk prefers a methane engine if the Defense Department decides to pursue a next-generation liquid rocket engine program.
Musk said a next-generation engine should be methane because it has a higher specific impulse capability than kerosene, which fuels the Russian-made RD-180 engine currently used in many national security space launches. Specific impulse determines the thrust of a rocket and indicates engine efficiency. An engine with a higher value of specific impulse is more efficient because it produces more thrust for the same amount of propellant.
SpaceX is producing a methane next-generation engine of its own called Raptor. Musk said the company has done a “fair bit” of advanced work on a methane engine and has tested parts of it at NASA’s Stennis Space Center in Mississippi. Musk said SpaceX might be interested in pursuing a next-gen engine program, depending on the parameters.
“If you’re not a hydrogen engine, the next best thing in terms of (specific impulse) is methane,” Musk told reporters Tuesday at an event in downtown Washington. SpaceX displayed its Dragon V2 space capsule for an East Coast audience. “I think that’s probably the way to go. I wouldn’t try to recreate sort of Russian ’80s technology, which is what the RD-180 is.”
Debate is taking place on Capitol Hill and inside the Pentagon as to which approach DoD should take to resolving its reliance on the RD-180. One option is replicating the RD-180 itself. Another is pursuing a next-generation liquid rocket engine and a rocket to accompany it. A blue ribbon DoD study panel in May recommended pursuing a liquid oxygen (LOX) oxidizer/hydrocarbon fuel rocket engine and pursuing it quickly. Hydrocarbon include gases like methane. The House Appropriations Committee (HAC) approved $220 million toward a next generation engine for fiscal year 2015 with the engine ready no later than FY ’22 (
Another reason to not replicate the RD-180, Musk said, is because he believes the Atlas V launch vehicle’s days are numbered. The Atlas V, developed by Lockheed Martin [LMT] and used by United Launch Alliance (ULA), a joint venture of Lockheed Martin and Boeing [BA], debuted in 2002.
Musk said he doesn’t understand why SpaceX’s certification with the Air Force to become eligible to compete for Evolved Expendable Launch Vehicle (EELV) cores is taking so long. SpaceX last summer signed a Cooperative Research and Development Agreement (CRADA) with the Air Force to certify its Falcon 9v1.1 launch vehicle. This agreement enables the Air Force to evaluate SpaceX’s launch system. Currently, only ULA is certified to carry national security payloads.
SpaceX, as part of its CRADA, fulfilled three missions. The Air Force has certified one mission, SpaceX is awaiting the results from the other two.
“Falcon 9 obviously works,” Musk said. “It’s not that the Air Force is changing the design of the rocket. They’re really just learning about it.”
Musk said he was undecided when asked if the Air Force was deliberately slowing the certification process as retaliation for SpaceX suing the service to force it to compete its “block buy” of 35 launch cores to ULA. The Air Force in 2013 awarded the block buy to ULA with the promise it would compete up to 14 cores to new entrants. The service earlier this year decided to cut the competed portion in half to seven, or perhaps, eight.
“It doesn’t seem like it should take this long for experts in the launch business to understand how a rocket works, which is all the certification process is,” Musk said.
Outgoing Air Force Space Command (AFSPC) chief Gen. William Shelton said in May the service is spending $60 million with 100 people working toward certification while calling the SpaceX launches “openers” for the process. Shelton said beyond the launches is process analysis and ensuring an auditable financial system. Certification is expected around the December/January timeframe, he said.
“All those things have to come together to certify a competitor to compete,” Shelton told reporters at the Space Symposium in Colorado Springs, Colo. “It’s very difficult to pick up the pace on that. I think SpaceX would have a hard time going faster than we are right now.”
Third-party launch indemnification has not been an issue for SpaceX, Musk said. Third-party indemnification is a term for the total amount of money the federal government would be responsible for paying beyond private insurance in case of public, or third-party, damages from a catastrophic commercial launch accident. In anticipation of such event, a launch company must purchase a fixed amount of insurance for each launch per calculation by the FAA.
The Government Accountability Office (GAO) testified earlier this year that indemnification helps keep United States commercial space launch competitive because competitors like Russia, China and France put no upper limit on the amount of their coverage while in the United States, coverage stops at about $3 billion per launch (Defense Daily, Feb. 5). Congress in the 2014 omnibus spending bill extended third-party indemnification through the end of 2016.
Musk said what’s problematic for SpaceX is that the Russians are its toughest competitors on the international launch market and yet the Air Force sends Russia “hundreds of millions of dollars” for Russian rocket engines.
“So not only do we not have access to our own national launch capability, but our own Air Force is funding the Russians to compete against us,” Musk said. “It’s super messed up.”