The crew test flight of the Boeing Starliner will proceed to launch on June 1 following a joint decision from NASA and Boeing’s project teams.
Both groups polled “go” for the launch after large-scale fixes were applied by the two agencies and rocket partner United Launch Alliance over recent weeks.
The Boeing Starliner crew test flight will launch astronauts Butch Wilmore and Suni Williams to the International Space Station where they will remain for a week before returning to Earth.
The two have remained in quarantine since the first launch attempt on May 6 was scrubbed.
An oxygen pressure regulation valve fault was detected on the Centaur second stage of the ULA Atlas V rocket, which led to the postponing of the first launch.
ULA replaced the valve on May 11, before repressurising and purging the liquid oxygen tank’s system.
A helium leak was also found in the Starliner service module, which required NASA and Boeing to repair the spacecraft itself. According to NASA, a pressure test performed on the faulty flange on a reaction control system thruster concluded no risk was posed to the flight.
Last week, NASA’s Commercial Crew Program manager Steve Stitch said the delays were required to reach the joint “go” vote from NASA and Boeing, with the new launch window starting at 12:25pm USEDT on Saturday 1 June. Further launch windows are available on June 2, 5 and 6.
“It has been important that we take our time to understand all the complexities of each issue including the redundant capabilities of the Starliner propulsion system and any implications to our Interim Human Rating Certification,” said Stich.
Boeing’s Starliner is part of the NASA Commercial Crew program, where private companies are contracted to taxi astronauts to and from the ISS.
NASA, Boeing and ULA are due to hold a pre-launch press conference on Friday 31 May local time to provide a troubleshooting overview.