The U.S. Air Force is looking to lock in its launch providers for national security satellite missions to take place between 2022 and 2026, and the bids for this so-called “Phase 2” procurement contract are now in. The field of competitors looking to become one of the two companies chosen is a who’s who of U.S. commercial launch providers at the moment, including SpaceX, Blue Origin, ULA and Northrop Grumman.

Both Northrop Grumman and Blue Origin are new entrants in this particular launch contracting area, while SpaceX and ULA are existing providers that handle U.S. national security missions. SpaceX additionally has a bit of a head start, since its Falcon rockets are the only proven, certified launch vehicles included in the bids submitted, while ULA has offered up its new Vulcan Centaur, which is tailor-made for the job but not yet certified and flight-proven; the others are still seeking certification.

“SpaceX means to serve as the Air Force’s long-term provider for space launch, offering existing, certified and proven launch systems capable of carrying out the full spectrum of national security space launch missions and requirements,” said SpaceX COO and president Gwynne Shotwell in an emailed statement, regarding this new bid.

SpaceX clearly sees its Falcon launch system as a key competitive advantage, as it’s flying currently for USAF and national security missions — the company says that this represents the lowest risk for the government overall in terms of providers for this mission, and with known costs, as well.

The Air Force will make its final selection about the two winning providers in 2020.