UPDATED Dec. 5, 3:53 p.m. EDT

WASHINGTON — The U.S. House Science Committee is set to consider a bill that would allow contractors on NASA’s biggest human spaceflight programs — the international space station, Space Launch System (SLS) and Orion crew capsule — to tap into more than $500 million dollars in funds set aside to cover program termination liabilities.

The measure also would bar NASA from terminating any of these programs without prior legislative approval. Federal agencies typically are able to unilaterally cancel programs at their own discretion.

The bill, H.R. 3625, was introduced Dec. 2 by Rep. Mo Brooks (R-Ala.), whose Huntsville, Ala., district includes the Marshall Space Flight Center, which is managing the SLS project for NASA.

At press time Dec. 5, Rep. Donna Edwards (D-Md.), ranking member of the House Science space subcommittee, was trying to amend Brooks’ bill to add the James Webb Space Telescope to the list of programs entitled to tap into termination liability reserves, and to be afforded protection from unilateral cancellation.

The House Science Committee was originally scheduled to vote on Brooks’ proposal Dec. 5, but Rep. Lamar Smith (R-Texas), the committee’s chairman, delayed consideration of the measure until the week of Dec. 9. The bill had 14 co-sponsors, including Democrats and Republicans, as of Dec. 5.

Boeing Space Exploration of Houston is prime contractor on the space station and is supplying the cryogenic rocket stages and avionics for the congressionally mandated SLS, which in early configurations will use five-segment, solid-fueled strap-on boosters made by ATK Launch Systems of Magna, Utah. Lockheed Martin Space Systems of Denver is prime contractor on the Orion Multi-Purpose Crew Vehicle, which would launch atop the heavy-lift SLS on deep-space missions. Northrop Grumman Aerospace Systems of Redondo Beach, Calif., is NASA’s prime contractor for the James Webb Space Telescope.

Brooks’ bill would change U.S. law to give these companies access to so-called termination liability funding, which government contractors typically must set aside to cover expenses that would arise should an agency opt to cancel a program. The measure would effectively void the termination liability provisions in existing SLS, Orion and space station contracts and make clear that Congress would appropriate funds to cover termination costs should NASA eventually elect to cancel the programs.

However, the bill also says that NASA cannot cancel these programs in the absence of signed legislation authorizing the agency to do so.

Brooks told SpaceNews Dec. 4 that contractors for the station, SLS and Orion programs have set aside more than $500 million in combined termination liabilities. The money, he said, would be better spent on these programs now.

“Given the financial difficulties that all federal government agencies are facing, anything you can do to free up unused resources is a benefit,” Brooks said.

A House source said Brooks’ bill enjoys bipartisan support in the House Science Committee. If approved in committee, the bill would reach the House floor no sooner than January, this person said.

In total, NASA spends roughly $3 billion a year on SLS and Orion development, including administrative and technical support from other NASA centers, and ground infrastructure improvements at the rocket’s launch site at the Kennedy Space Center in Florida.

The annual space station budget is nearly $3 billion, including crew and cargo transportation services.

SLS and Orion are being built with a mix of surplus space shuttle parts and hardware designed for the Constellation Moon exploration program created by NASA in 2005 under the administration of then-President George W. Bush and canceled in 2010 by President Barack Obama.

After the White House shut down the program, Congress ordered NASA to build SLS and Orion, and to utilize the contracts that ATK, Boeing and Lockheed won during Constellation-era competitions to do so.

ATK in the past complained about the requirement to set aside reserve funding on SLS, saying it was causing the program to be underfunded.

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