Barbara Mikulski is worried. The powerful Democratic U.S. senator from Baltimore has seen a lot of big government programs go sour because the funding dried up before they were finished, and now that she is chair of the Senate Appropriations subcommittee that funds NASA, she says she is afraid it is about to happen to the whole U.S. space program.

“We're going to get to the end of the day with a fiscal quagmire, unresolved, with the space agency and DOD [Defense Department] and other agencies underestimating what it's going to take, and then we end up with programs that falter or sputter,” she says. “NASA's mission faltering or sputtering really can blow the whole program.”

The source of Mikulski's fiscal- quagmire nightmare is sequestration, the automatic across-the-board federal-spending cuts that Congress set up to force itself to reduce rationally. She and Sen. Richard Shelby of Alabama, the ranking Republican on her subcommittee, will tell anyone who will listen that it is time to return to “regular order,” which means federal funds will be allocated, authorized and appropriated like they were before sequestration. The senators represent states with major NASA field centers—Goddard and Marshall, respectively—and the regular order would make it a lot simpler to continue nurturing the high-dollar programs that mean jobs and business for their constituents.

NASA Administrator Charles Bolden says the agency has been able to keep its major programs on schedule under sequestration this year without furloughing employees by holding down costs whenever possible. The agency drafted its $17.7 billion budget request for fiscal 2014 on the assumption that Congress and the White House would be able to figure out a better way to handle budget cuts.

Mikulski and Shelby consider that budget request inadequate, particularly in the funding for the heavy-lift Space Launch System (SLS) that is intended to take humans beyond low Earth orbit. NASA wants $820 million to keep at least two competitors in the running for a commercial route to the International Space Station, but many lawmakers would like to see $300 million of that transferred into the $1.385 billion SLS request for fiscal 2014.

At Marshall Space Flight Center, work on the big new rocket appears to be going well. Preliminary design review is scheduled to begin June 17, and managers do not see any show-stoppers. A lot of the hardware has been repurposed from other flight vehicles, and getting to this point has had more to do with making the components work together in new configurations rather than the time-consuming detail work of developing new engines.

For example, the first four SLS flights will use surplus RD-25D space shuttle main engines, four at a time. The engines flew three at a time on much shorter vehicles than the towering SLS, which also will accelerate faster off the pad. That will create inlet pressures on the order of 300 psi, a higher level than the RD-25D can accommodate with only minor modifications, according to SLS chief engineer Garry Lyles. But the test stands at Stennis Space Center can only deliver 260 psi at the inlets, so the engines will be throttled back on the initial flights to hold the inlet pressures at 260 psi, Lyles says. The test facilities will be uprated when the follow-on RD-25Es come on line, he says.

Meanwhile, at Michoud Assembly Facility in New Orleans crews have removed the cells where large sections of foam were applied to shuttle external tanks (top photo), making way for the Vertical Assembly Facility that will house the largest friction stir-welding machine ever built, to join SLS tank and dome assemblies once the final design is set.

There is a whole shelf-full of studies, going back decades, that conclude the best way to move humans beyond low Earth orbit is with a heavy-lifter like the SLS. Alternate methods—smaller launchers and in-space refueling depots, for example—fly in the face of the lessons learned with the dangerous and time-consuming process of building the ISS in orbit, and would require new technologies that will cost even more money and time. Instead, NASA has decided it wants $105 million in new funding to begin work on an asteroid-capture mission that would give a focus for near-term human exploration beyond low Earth orbit (AW&ST April 29, p. 36).

Mikulski is right. “Faltering and sputtering” now could indeed “blow the whole program.” Congress already has shielded air traffic control from sequestration. Is the U.S. space program any less important than on-time arrivals for air travelers?