Although the supply of Russian-built RD-180 engines that power the first stage of the Atlas V do not appear to be in the same level of jeopardy as feared earlier this year—United Launch Alliance took delivery of two of those engines last week—the US Air Force is starting to lay the groundwork for development of a domestic replacement engine.
Last week, the Air Force Space and Missile Systems Center (SMC) issued a request for information (RFI) regarding development of a new booster engine. “The Air Force has relied upon foreign sources for booster propulsion systems in the past,” the RFI states, making no overt link to the latest tensions about RD-180 access. “However, consistent with the 2013 National Space Transportation Policy, we are pursuing alternative domestic capability.”
The RFI actually goes beyond the engine itself to interest in alternative launch systems in general: “The Air Force is open to a range of possible options including but not limited to: a replacement engine with similar performance characteristics to currently used engines, alternative configurations that would provide similar performance (such as a multiple engine configuration) to existing EELV-class systems, and use of alternative launch vehicles for EELV-class systems.”
The RFI features two sets of questions, one for those interested in providing new engines and one for new launch systems. The first set of questions asks how companies would replace the RD-180, including whether such an engine could be developed for multiple users. The second set of questions asks how companies would replace the capability offered by the Atlas V, while also asking if they believe a multi-user engine could be developed. Both sets of questions also ask for thoughts on how the government should acquire a new engine or launch system, including their interest in a “shared investment” approach with the government to fund development.
Responses to the RFI are due to the Air Force on September 19, with a two-day “industry day” planned at SMC on September 25-26. The next steps may depend on what direction, and funding, Congress provides the Air Force: House and Senate authorization and appropriations bills have provided differing levels of support for development of an RD-180 replacement.