WASHINGTON — The first crewed flight of Boeing’s CST-100 Starliner spacecraft is a step closer to launch after completing a major pre-launch review April 25.

NASA announced at an April 25 briefing that, at the completion of the two-day Flight Test Readiness Review, officials approved plans to proceed with the Crew Flight Test (CFT) mission, with a launch scheduled for 10:34 p.m. Eastern May 6 from Cape Canaveral’s Space Launch Complex (SLC) 41. Backup launch opportunities are available May 7, 10 and 11.

“I can say with confidence that the teams have absolutely done their due diligence,” said NASA Associate Administrator Jim Free. “There’s still a little bit of closeout work to do, but we are on track for a launch.”

That remaining work is what Steve Stich, NASA commercial crew program manager, described as “a couple standard things” for pre-launch preparations. They include replacing a valve in a liquid oxygen replenishment system at SLC-41 and performing additional analysis on a part of the parachute system that releases a cover called the forward heat shield so that the drogue and main parachutes can deploy. That additional analysis is being done “out of an abundance of caution,” he said.

The launch also depends on the readiness of the International Space Station. A cargo Dragon spacecraft, CRS-30, must undock from the station, after which the four members of the Crew-8 crew will board their Crew Dragon spacecraft and move it from the forward to the zenith port on the Harmony module. That will free up the forward port for Starliner, which is currently only approved for docking to that port.

The CRS-30 Dragon spacecraft was scheduled to undock from the ISS on April 26 but weather at splashdown locations has delayed its departure to at least April 28. Dana Weigel, NASA ISS program manager, said it was too early to say how much more the CRS-30 departure could be delayed without forcing a Starliner launch delay, but said the Starliner launch could remain on schedule so long as the Crew Dragon port relocation takes place by May 2 or 3.

The CFT mission is intended to test spacecraft systems with astronauts on board after two previous uncrewed flights, the second nearly two years ago. Boeing had planned fly CFT last year but was forced to delay the mission because of problems with parachute system components as well as to remove tape used in wiring systems that was found to be flammable.

NASA astronauts Butch Wilmore and Suni Williams will fly Starliner, docking with the ISS about a day after launch. They will remain on the station for over a week before undocking to return to Earth, landing in the southwestern United States. They will go through a set of test objectives ranging from confirming the performance of the spacecraft’s life support system to flying it under manual control.

Mark Nappi, vice president and program manager for Boeing’s commercial crew program, deflected questions at the briefing about the long-term future of Starliner, which currently only has a contract with NASA to launch six post-certification, or operational, missions to the ISS after the CFT mission. “The focus again is on CFT. That really has all of our attention at this point,” he said.

The NASA contact, he noted, carries Boeing through the end of the decade and the projected retirement of the ISS, assuming one flight a year. “We’ve got plenty of time to think what’s after that, and we will do that, but right now the focus is on CFT.”

He added he felt no pressure to “score a win” with the test flight given the problems facing Boeing’s commercial airplane unit. “We signed up to go do this and we’re going to go do it and be successful at it,” he said. “I don’t think of it in terms of what’s important for Boeing as much as I think of it as in terms of what’s important for this program, to follow through with the commitments we made to our customers.”

At an April 17 meeting of NASA’s Aerospace Safety Advisory Panel, Susan Helms, a former astronaut and current chair of the panel, said her committee was confident that safety was at the forefront of those involved in the mission.

“It’s the panel’s view that NASA has an appropriate, mature risk management framework in place to address the challenges of this Crew Flight Test of the Starliner, and that NASA’s safety culture appears to be healthy and equal to the task,” she said, while adding that NASA and Boeing needed to be ready for any contingencies during the test flight.

That extended to the astronauts flying on Starliner. “Why do we think it’s as safe as possible?” Wilmore said to reporters after he and Williams arrived at the Kennedy Space Center April 25. “We wouldn’t be standing here if we didn’t.”

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...