Gen. John Hyten, commander of Air Force Space Command said in 2013 — as vice commander — sequestration cuts forced the service to lay off about half of its space operations contractor workforce. Credit: Xinia Productions/Jose Morales

NATIONAL HARBOR, Md. — When Jeff Bezos, the founder of Blue Origin, and Tory Bruno, the chief executive of United Launch Alliance, called the U.S. Air Force’s top space official to tell him about their partnership on a new rocket engine, they found an engineer who is a fan of methane-fueled propulsion technology but also aware of the challenges the companies face.

Gen. John Hyten, commander of Air Force Space Command, told reporters Sept. 17 here that he was excited about the Blue Origin-ULA partnership on a replacement for the RD-180 engine that powers ULA’s Atlas 5 rocket, but wondered when the new engine might be ready.

Blue Origin says its planned BE-4 engine has been in development for three years and builds upon the company’s smaller BE-3, which has racked up more than 10,000 seconds of firing time on the test stand. Bezos and Bruno said the BE-4 is fully funded and will be ready to fly in four years.

“I’m excited to have more U.S. competition in the business,” Hyten said. “I look forward to getting into the details and finding out more about what it really is. I’m a big fan of methane technology. I’m a big fan of hydrocarbon technology.”

In contrast to the Russian-built RD-180, which is fueled by kerosene, the BE-4 will be fueled by liquefied natural gas, which is similar to methane. U.S. companies have been tinkering with methane propulsion for years.

“That kind of technology has been exciting to me personally for a long time,” Hyten said. “They’ve worked it in a number of areas, but nobody’s been able to make it real yet. Not at the scale they’re looking at. That’ll be the challenge.”

Bezos and Bruno called Hyten the morning of Sept. 17, less than two hours before going public with their partnership. During the phone call, Bezos touted Blue Origin’s three years of work to date on the BE-4, Hyten told reporters.

“I don’t really know what that means,” Hyten said. “Three years of development is better than starting at ground zero. If we start at ground zero to build a new engine in the hydrocarbon technology area we’re five years away from production, roughly, maybe four, maybe six. The one thing you would have to do is spend the next year or two driving down the technology risk so you can actually build that. That is the significant challenge from starting from ground zero.”

Both kerosene and liquefied natural gas are hydrocarbon fuels.

Amid concerns about the future availability of the RD-180 and the health of the U.S. rocket-making industrial base, the U.S. government is considering various options to ensure future access to space and has solicited ideas from industry.

Industry’s widely varied responses will be evaluated “at the highest level of the Pentagon,” including by Frank Kendall, the Defense Department’s acquisition czar, Hyten said. Bill LaPlante, the assistant secretary of the Air Force for acquisition, told reporters Sept. 16 the service also hopes to have an acquisition plan for a new launch system by the end of 2015.

LaPlante said the Defense Department is open to different technologies and teaming arrangements that explore “the art of the possible” to develop the new engine.

“We deliberately kept it not restricted to a certain engine type,” LaPlante said. “We’ll look at solids, look at liquid hydrogen, we’ll look at [liquid-oxygen]/hydrocarbon.”

Meanwhile, a group of 18 House members, including six from Alabama, where ULA assembles the Atlas 5, wrote President Barack Obama saying they supported a new hydrocarbon rocket engine. The House has proposed spending as much as $220 million for such an effort next year, although Washington insiders say it likely will receive much less money, if any at all.

“We are especially interested in a path forward which leads to a fully developed engine no later than 2019, available to multiple launch companies,” the letter said.

The letter also warned against the White House’s proposed strategy of examining different technologies and components before investing heavily in a specific engine-developent program.

“Much of the initial risk reduction work has been done and we believe it is time to finish the job,” the letter said. “Significant dilution of the monies to other technology efforts runs the risk of delaying the engine development program and perpetuating U.S. reliance on Russian launch engines.”

Mike Gruss covers military space issues, including the U.S. Air Force and Missile Defense Agency, for SpaceNews. He is a graduate of Miami University in Oxford, Ohio.