WASHINGTON – The U.S. Defense Department, which is just now introducing competition into the national security launch market, is simultaneously studying whether to award some contracts on a sole-source basis, presumably to incumbent United Launch Alliance, to ensure that it has at least two rocket families at its disposal for the foreseeable future, a Pentagon spokesman said Oct. 8.

“If it is deemed necessary in order to maintain two viable sources of launch services, sole source allocation of some launches will be one of the options examined,” Navy Lt. Cmdr. Courtney Hillson said in an Oct. 8. statement.

Retired Gen. Larry Welch, a former Air Force chief of staff, recommended as much earlier this year and Air Force Secretary Deborah Lee James did not rule out the sole-sourcing of some launch contracts in an Oct. 8 interview with SpaceNews.

In the statement, Hillson said Deputy Defense Secretary Bob Work has asked the Pentagon’s acquisition czar, Frank Kendall, to “further examine a range of options” to ensure the Defense Department has access to two launch service providers. Results of Kendall’s study are expected before the end of the year, the statement said.

It seems likely that any sole-source contracts would go to ULA, the Air Force’s longtime monopoly launch services provider, which is now facing a stiff competitive challenge from SpaceX, whose prices might be difficult to match.

Congress mandated last year that the Air Force by 2019 end its reliance on the Russian-made RD-180 rocket engine that powers the first stage of ULA’s most competitive rocket, the Atlas 5. ULA also operates the Delta 4 rocket that is not affected by the ban, but intends to phase out all but the heaviest version of that vehicle in the coming years due to its high cost.

The RD-180 ban is structured such that ULA only has a limited number of Atlas 5s available for the competitive phase of the Air Force’s Evolved Expendable Launch Vehicle program, now underway. The exact number is still a matter of debate.

Denver-based ULA, a Boeing-Lockheed Martin joint venture, has 29 RD-180 engines on order from its Russian supplier. Fifteen of those engines are for Air Force launches already under contract and are unaffected by the ban.

Another five have been exempted by the National Defense Authorization act of 2015, the law that imposed the ban in the first place, but ULA says these have been allocated already to nonmilitary customers — an assertion the Air Force has questioned. The Air Force also points out that the compromise version of the NDAA for 2016 would exempt four additional engines, although that bill faces a presidential veto threat over unrelated provisions.

Regardless, ULA says it needs unrestricted access — the ban only affects national security missions — to at least 14 more RD-180s to stay competitive until its next generation Vulcan rocket begins flying around 2020. Air Force officials have put the number at 18-22.

The Vulcan’s first stage would be powered by the BE-4 engine being developed by Blue Origin of Kent, Washington. Congress also has allocated substantial funding to replace the RD-180 with a U.S.-built alternative, but that program has been slow to get started and ULA in any case says its mind is made up on the BE-4, which Blue Origin is funding on its own.

Meanwhile, the first Air Force launch competition in a decade formally began Sept. 30  with the release of a request for proposals to launch a GPS 3 navigation satellite in 2018. Bids are due Nov. 16, but ULA says that barring relief from the ban it will not participate, presumably ceding the contract to Hawthorne, California-based SpaceX.

Emily Shanklin, a SpaceX spokeswoman, declined to comment on the statement.

The current law allows the Air Force to request a waiver from the ban from the secretary of defense if U.S. national security is at stake and no other affordable launch option is available. However, the GPS 3 mission does not appear to meet the criteria, and in any case the Pentagon does not intend to pursue a waiver at this time, Hillson said.

While the Defense Department remains “committed to competition as a way to control cost,” it is prepared to suspend that philosophy in certain instances rather than see ULA driven from the market.

“The Department cannot be in the risky position of relying on only one source of space launch for critical national security satellites that must be launched reliably and on schedule,” the statement read. “With only one source of launch services a failure could lead to a long gap in access to space.”

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.