WASHINGTON — NASA will give companies greater choice in the type of contract to use for producing a deorbit vehicle for the International Space Station.

In a procurement notice posted Dec. 5, NASA announced it would allow companies the choice of using either firm fixed price or cost plus incentive fee contract structures for both the design and the production of the U.S. Deorbit Vehicle (USDV).

When NASA issued the original request for proposals (RFP) for the vehicle in September, the agency gave bidders a choice. They could propose to develop the vehicle using a cost-plus contract and then produce it under a fixed-price contract, a so-called “hybrid” approach. Alternatively, they could propose doing both development and production under fixed-price contracts.

The revised approach now adds an option to perform both the development and the production under cost-plus contracts. NASA, in both the procurement notice and a blog post, did not disclose the reason for the change.

NASA has also revised the deadline for submitting proposals. The agency originally requested proposals to be submitted by Nov. 17, with a single award expected in April 2024. NASA later extended the proposal deadline to Dec. 14. With this change, NASA has pushed back the deadline to Feb. 12, with an award expected in late May or early June.

The USDV will be used to handle the final phases of a controlled reentry of the ISS at the end of its life. NASA requested $180 million for the vehicle in its fiscal year 2024 budget proposal in January, with officials saying at the time they projected the vehicle’s total cost to approach $1 billion.

The revised RFP includes both “desired” and “required” delivery dates for the USDV. The desired delivery date for the vehicle is Aug. 1, 2028, for a launch four months later, while the required delivery date is May 1, 2029, also for launch four months later. Proposals that do not meet the required delivery date “will be considered nonresponsive and rejected.”

That delivery schedule would support deorbiting of the ISS in 2030, the current planned retirement date for the station by NASA and its Western partners. Russia has, so far, only committed to ISS operations to 2028. The RFP, though, includes pricing options for storing the USDV on the ground in a “Dwell facility” through 2035.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...