WASHINGTON — Members of a NASA safety panel expressed continued concern about quality issues with Boeing’s commercial crew spacecraft while cautiously supporting SpaceX’s plans to fly reused spacecraft on future crewed missions.
During a July 23 teleconference by the Aerospace Safety Advisory Panel, members discussed several reviews of issues with the uncrewed flight of Boeing’s CST-100 Starliner spacecraft last December. NASA announced July 7 it had completed its reviews of that Orbital Flight Test (OFT) mission, which resulted in 80 recommendations specific to the flight and several more from a separate “high-visibility close call” review carried out earlier this year by NASA.
All of the recommendations specific to Starliner, including software issues that accounted for the majority of those recommendations, will need to be completed and approved before a second OFT mission, said Don McErlean, a member of the panel. He noted NASA has augmented its commercial crew software team “to significantly increase insight and oversight” into the vehicle’s software development.
Those actions “should significantly reduce the risk to OFT, Crew Flight Test, and further [commercial crew program] flights,” he said. Crew Flight Test, or CFT, would be a crewed test flight of the spacecraft carrying two NASA astronauts and one Boeing astronaut.
However, he said the panel still had concerns about the overall Starliner program. “Despite this progress, which is definite and, in fact, measurable, the panel continues to be concerned about quality control problems that seemingly have plagued the Boeing commercial crew program,” he said. “This is still an issue that the panel will continue to watch closely as OFT and, later, CFT, are conducted.”
The panel made no specific recommendations beyond asking NASA’s commercial crew program to ensure there is a balance between schedule and work on the vehicle. NASA has not set a schedule for the second OFT mission, but has suggested the flight could take place late this year, with CFT following in the spring of 2021.
Patricia Sanders, chair of the panel, was skeptical that Starliner will be ready to fly NASA astronauts soon, concluding it was “still a ways off before we have two fully functioning, operational vehicles.”
Concerns about the software issues with Starliner have extended to other NASA programs. Susan Helms, a former astronaut who is a member of the panel, said NASA’s exploration systems development (ESD) programs are “very engaged” in the review, particularly regarding software development recommendations that could apply to its own programs.
NASA “is applying the notable lessons learned from that investigation to the software program management of the ESD program,” she said, although the details about effort were deferred to a future panel meeting.
SpaceX reusability
While the safety panel was critical of Boeing’s work on commercial crew, it praised SpaceX for the success so far of its Demo-2 Crew Dragon mission to the International Space Station. “NASA and SpaceX are most certainly to be congratulated for the Demo-2 launch,” McErlean said.
That mission, he acknowledged, is not yet over, with NASA planning a splashdown off the Florida coast Aug. 2, depending on weather conditions. McErlean noted that this spacecraft has a “very limited wind margin” that will complicate the landing. As a result, NASA now has identified seven locations off the Florida coast, up from three originally identified. They are located offshore from Cape Canaveral, Daytona Beach, Jacksonville, Panama City, Pensacola, Tallahassee and Tampa.
A successful landing for Demo-2 will allow NASA and SpaceX to turn their attention to the first operational Crew Dragon mission, Crew-1. NASA said in a July 22 media advisory it anticipated a launch no earlier than late September.
The Crew-1 mission will use both a new Falcon 9 booster and Crew Dragon spacecraft, but later missions will use previously flown hardware. NASA approved a contract modification in May that allows SpaceX to reuse boosters and capsule starting on the Crew-2 mission, which would launch in 2021.
McErlean said NASA expects that the Crew-2 will use the Falcon 9 booster that launches Crew-1, and the capsule from the ongoing Demo-2 mission.
“This is the first time that we will have reuse of hardware in a human-carrying capsule,” he said. “In this case, Crew-2 will be fully utilizing the SpaceX reuse philosophy.”
Allowing boosters and spacecraft to be reflown on crewed missions will require changes to NASA spacecraft certification procedures, he cautioned, as well as handling SpaceX’s approach to “constantly evolving” vehicle designs to incorporate improvements and other changes.
“Given the SpaceX approach to hardware upgrades, NASA has to decide by what processes it will continue to monitor vehicle and system changes to ensure that those changes still remain in an appropriately certified safety posture for human spaceflight operations,” he said.
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