In a memorandum sent Tuesday to the US Secretary of the Air Force, the Department of Defense's deputy inspector general for policy and oversight, Randolph R. Stone, announced his office had begun an investigation "regarding assertions" made by a former United Launch Alliance executive.

The executive, Brett Tobey, resigned from the Colorado-based company last week after making comments about ULA struggling to compete on launch costs with another rocket company, SpaceX. Tobey also said the government "had bent over backwards to lean the fill to our advantage," when it came to awarding launch contracts.

"At the request of the Secretary of Defense, the OIG DoD has opened an investigation regarding assertions made by United Launch Alliance’s former Vice-President of Engineering relating to competition for national security space launch and whether contracts to ULA were awarded in accordance with DoD and Federal regulations," Stone writes in the memorandum, obtained by Ars Tuesday evening.

United Launch Alliance, which has been the sole provider of national security payload launches, characterized Tobey's comments to a University of Colorado-Boulder seminar as inaccurate. However, Tobey's comments appear to offer insight into a large company trying to compete with a more nimble, smaller firm. For the last two years, SpaceX has been seeking the right to bid on military launches and said it can offer a lower cost alternative to getting spy satellites and other sensitive payloads into space.

In late 2015, after the military had certified SpaceX's Falcon 9 as reliable enough for national security launches, the Air Force asked for bids to launch a GPS 3 satellite in 2018. When ULA did not bid on the contract, effectively ceding it to SpaceX, ULA said it was unable to submit a bid because of contract requirements and the limitations Congress had imposed on its rocket's Russian-made RD-180 engine.

However, in his remarks to the Colorado students, Tobey offered a different view of that contract. "ULA opted to not bid that," he said. "The government was not happy with us not bidding that contract because they felt that they had bent over backwards to lean the fill to our advantage. But... we saw it as a cost shootout between us and SpaceX. So now we're going to have to figure out how to bid these things at a much lower cost. And the government can't just say ULA has a great track record, they've done 105 launches in a row with 100 percent mission success, and we can give it to them on a silver platter even though their costs are two or three times as high."

The investigation will include site visits, interviews, and documentation review with Department of Defense and ULA personnel, Stone's memorandum says.