Debate over this year’s US defense budget centered around the purchase of Russian-made RD-180 rocket engines. Designed and manufactured by NPO Energomash, the rockets are a key element of the Atlas V launch vehicles, providing a cost-effective alternative to the Delta IV, Washington’s only other current option.
Arizona Senator John McCain led a charge to ban the Russian-made engines, citing security concerns.
Now McCain has backed down. Reaching a compromise, the Senate Armed Services Committee presented an amendment to the defense policy bill that places an end date of 2022 for the RD-180’s use, and limits the number that the US military can purchase to 18.
"I supported this compromise because it contains a legislative cutoff date for the use of Russian rocket engines," McCain said in a statement.
"It does not alter other important space launch provisions in the NDAA [National Defense Authorization Act]. It provides for a sustainable path to achieve the broadly shared goal of assured access to space, competition in national security space launch, and ending our dependence on Russian engines."
The amendment was presented by Bill Nelson, a Democratic senator from Florida.
"We never want to get to the position that we just have one rocket company, because if something happened, you want to have a backup," Nelson said, according to Defense News.
"We have got to get satellites into space to protect our national security, and we’ve got to do it over this period of time from now until the end of 2022."
The US government is hoping that American companies like SpaceX will perfect their own rockets. For the time being, the Delta IV rocket is the only viable US-made option, but its hefty price tag led to charges that abandoning the cheaper RD-180 would be financially irresponsible.
"Using Delta when an Atlas will do is like burning $100 million on the back lawn for fun. That’s how big the price difference could be for some missions," Loren B. Thompson, a senior defense analyst with the Lexington Institute, said.
A Delta IV launch costs approximately 35% more than an Atlas V launch.
"If Delta gets grounded like SpaceX rockets were last year, and Russian engines can’t be used, then there will be no way of orbiting satellites critical to America’s defense."
On Monday, Air Force Chief of Staff Gen. Mark Welsh told Defense News that he thought the debate had been "healthy" and "positive."
"We don’t have to agree. Our job is to provide the best military advice we can give based on the reality of the time. And if Congress disagrees with it, they make a decision about what they will authorize and appropriate, and we move onto the next annual cycle," he said.
"Everyone wants to get off the RD-180 engine, the Russian-built engine, as soon as we possibly can. Everybody wants the same things. But there are disagreements from all parties, on the best way to get from here to there."