LOGAN, Utah — Boeing has delayed the first flight of its CST-100 Starliner commercial crew vehicle with astronauts on board to no earlier than March 2024 as the company continues to work on issues with the spacecraft’s parachutes and wiring.
Boeing and NASA officials said in an Aug. 7 media briefing that they are making good progress on those issues, which they revealed more than two months ago, but that they still have several more months of work to complete before the vehicle will be ready to carry NASA astronauts.
One problem has been with “soft links” in the parachutes that were weaker than expected, preventing the overall parachute system from achieving the factor of safety required for crewed flights. “That has been redesigned by the team. They’re in the middle of testing that design,” Steve Stich, NASA commercial crew program manager, said on the call.
That testing will include a drop test scheduled for the latter half of November, said Mark Nappi, Boeing vice president and program manager for Starliner. That test will also verify an updated overall design for the parachute that had been intended for the first operational flight of Starliner, but will be pulled forward for this Crew Flight Test (CFT) mission.
Stich said a single test of the parachute will be sufficient, compared to a series of drop tests for a revision of parachutes during development of SpaceX’s Crew Dragon. “When we looked at the changes that we’re talking about, we felt like we only needed one test” to verify those changes, he said, which he described as much less significant than the earlier SpaceX parachute changes. “The design changes were, what I would say, minimal as opposed to what we had for Dragon, which was really a wholesale change in the canopy.”
Technicians have also been removing a tape used on wiring harnesses called P-213 that is flammable in some environments. Stich said that entries in a NASA database were “a bit inconsistent” about the tape’s flammability that led to its use in environments where it could pose a hazard.
Workers have removed about 85% of the tape in the upper part of the spacecraft. In the lower part of the spacecraft, some tape is hard to remove or could cause damage if its removed, said Nappi. Engineers have developed protective barriers and coatings, or can wrap the P-213 tape with acceptable tape, to mitigate the flammability hazard. “Based on the area, we’ll apply the right remediation technique.”
Neither NASA nor Boeing announced a new launch date for the CFT mission, which will send NASA astronauts Butch Wilmore and Suni Williams to the International Space Station for a brief stay. Before the parachute and wiring tape problems were announced, NASA had been targeting a late July launch of the mission, which has already suffered extensive delays.
Nappi said the critical path for getting Starliner ready for flight will be the parachute work. “Right now, based on the current plans, we’re anticipating that we’re going to be ready with the spacecraft in early March,” he said.
That does not, he added, mean that the CFT launch will take place in March. He said Boeing will have to work with NASA on ISS schedules, as well as United Launch Alliance on Atlas 5 launch schedules, to set a date. “We’ll work that throughout the next several weeks and see where we can fit in, and then we’ll set a launch date.”
Stich noted that March is typically when Roscosmos performs crew rotations using its Soyuz spacecraft, which could limit CFT opportunities that month. “We have not taken the vehicle readiness and mapped it into when we can find a date” that works with both the station and ULA, he said. “That’s really the next step.”
The delay of CFT into at least the spring of 2024 could push back the first operational, or post-certification, mission to 2025. Stich said it was too early to determine when Starliner could fly that mission. He suggested that mission could fly around the end of 2024, although crew rotation missions on Crew Dragon spacecraft are currently launching in February and August. “We would like to fly it as soon as we can.”
Boeing’s Nappi reiterated the company’s commitment to fly its contracted series of six post-certification missions, roughly once a year through late in the decade, even as the company’s losses on the Starliner program exceed $1 billion. The ISS is scheduled for retirement around 2030, but Nappi said there was time in that schedule to fit in the six flights by the end of the decade. “There’s no reason to change our plans.”
NASA, meanwhile, emphasized its desire to have a second commercial crew provider, with Starliner alternating with Crew Dragon. “We’ve got plenty of flights for Boeing to go fly, and we’re in good shape,” Stich said.
