The Boeing launch Starliner spacecraft traversed by stars on its first manned test flight is being pushed back to at least June 1 to give engineers more time to assess a small but persistent helium leak in the capsule's propulsion system and its potential impact on all phases of the flight, NASA announced Wednesday.
Already years behind schedule and more than a billion dollars over budget, the Starliner's launch path it's been surprisingly rockywith multiple problems leading up to its first crewed flight test, which is now slipping nearly a month past its May 6 target.
United Launch Alliance
This launch attempt was canceled due to problems not related to a valve on the United Launch Alliance Atlas 5 rocket that was quickly corrected. But the helium leak in the Starliner's service module, detected during the May 6 countdown, has proven more difficult to resolve to everyone's satisfaction.
At the time, NASA officials said the leak was within acceptable limits and would not have caused launch control on its own. But after additional inspections, and an unsuccessful attempt to eliminate the leak by tightening the bolts on a flange where it appeared to originate, mission directors began a more thorough analysis.
Helium helps pressurize the spacecraft's propulsion system, and if too much gas leaks out: the propellants used for launch aborts, in-orbit maneuvers to rendezvous with the International Space Station, and departure and re-entry, could be affected. Although the leak appears stable, NASA is looking for a “flight justification” that shows it won't get worse in flight.
“As part of this work, and unrelated to the current leak, which remains stable, teams are in the process of completing an assessment of the follow-on propulsion system to understand the potential impacts of the helium system in some scenarios of Starliner return,” NASA said in a statement. late wednesday
This will be the subject of a second flight readiness review in the coming days. Meanwhile, mission commander Barry “Butch” Wilmore and co-pilot Sunita Williams will remain at Johnson Space Center practicing procedures in high-fidelity flight simulators. They will fly back to Florida next week if mission managers order the Starliner for launch.
The June 1 launch, the same day that SpaceX could target for the next flight of its Super Heavy-Starship rocket, would be set for 12:25 p.m. EDT, about the time when Earth's rotation brings the Pad 41 at the Cape Canaveral Space Force Station. in Florida in the plane of the space station's orbit.
If all goes well, the crew would dock at the lab's bow port on June 2 and return to Earth with a landing at White Sands, New Mexico, on June 10. Assuming there are no major problems, NASA hopes to certify the Starliner for operational crew rotation. flights to the station starting next year, alternating with those of SpaceX Spaceship Crew Dragon.
But that will require a full “human rating certification” for the Starliner, and that will depend on the results of the crew's flight test.
“It has been important that we take our time to understand all the intricacies of each issue, including the redundant capabilities of the Starliner propulsion system and any implications for our interim human qualification certification,” said Steve Stich, program manager of NASA commercial crew.
“We will launch Butch and Suni on this test mission after the entire community has reviewed the teams' progress and flight justification” at the next flight readiness review, Stich added.
