Ongoing evaluation of a helium leak on Boeing’s Starliner spacecraft pressured NASA and Boeing to delay the Crew Flight Take a look at mission additional.
A weblog publish, issued late on Friday afternoon, introduced a brand new goal launch date for Starliner CFT with NASA astronauts Butch Wilmore and Suni Williams of no sooner than Saturday, Could 25, at 3:09 p.m. EDT (1909 UTC).
The spacecraft will launch atop an Atlas 5 rocket from United Launch Alliance to dock with the Worldwide Area Station for a roughly eight-day keep earlier than returning to Earth.
Heading right into a Could 6 launch try, a leak was detected within the pressurization system that permits the gas and oxidizer on the Starliner’s Service Module (SM) to circulation appropriately to their designated thrusters when known as upon. The SM options 28 response management system (RCS) thrusters and 20 orbital maneuvering and perspective management (OMAC) thrusters.
The helium leak was linked to a single RCS thruster and was decided to be inside flight limits on Could 6.
Nevertheless, through the countdown, a strain aid valve on the Atlas 5 rocket’s Centaur higher stage was performing up and the mission was scrubbed about two hours earlier than liftoff. The rocket was rolled again into ULA’s Vertical Integration Facility (VIF) the place the valve was changed, examined and cleared for flight.
Whereas contained in the VIF, Boeing determined to additional examine and take a look at the helium leak to offer better assurance that it wouldn’t impression the mission.
Groups introduced the spacecraft as much as flight strain on Could 15 and decided that “the [helium] leak within the flange is secure and wouldn’t pose a danger at that stage throughout flight,” NASA and Boeing stated in a joint weblog publish.
The replace additionally famous that “testing additionally indicated the remainder of the thruster system is sealed successfully throughout the whole service module.”
Helium is pressurized to a sure stage through the run-up to launch in addition to through the rocket’s ascent within the occasion that the thrusters and the launch abort engines can be wanted for an abort and a fast escape for the astronauts.
As soon as the spacecraft reaches orbit, it will vent off a number of the helium deliberately.
Whereas the testing this week had some constructive indications, Boeing and NASA determined to take extra time for Boeing “to develop operational procedures to make sure the system retains ample efficiency functionality and applicable redundancy through the flight.”
“As that work proceeds, NASA’s Business Crew Program and the Worldwide Area Station Program will take the following few days to evaluation the information and procedures to make a ultimate willpower earlier than continuing to flight countdown,” the weblog acknowledged.
Spaceflight Now reached out to NASA and Boeing for an interview relating to the replace. A NASA spokesperson stated there was no briefing deliberate till the usual pre-launch briefing late subsequent week. In the meantime, a Boeing spokesperson declined an interview, although presumably, could have a consultant take part within the forthcoming briefing. NASA didn’t reply to requests for interviews.
Following the Could 6 launch scrub, and whereas this work has been ongoing, Wilmore and Williams flew again to Houston, Texas, to be with their households and proceed coaching for the mission. They’re on account of return to Florida “nearer to the brand new launch date.”
The Starliner spacecraft was chosen alongside SpaceX’s Crew Dragon capsule to grow to be the 2 automobiles NASA would use to move its astronauts to and from the ISS. Boeing and SpaceX acquired $4.2 billion and $2.6 billion respectively for the event work and the primary six operation missions.
SpaceX launched its uncrewed demonstration mission in 2019 and the two-member crewed Demo-2 flight in Could 2020. Up to now, Dragon has flown 53 folks throughout 13 mission, 4 of which have been non-governmental personal flights.
Boeing’s Orbital Flight Take a look at in 2019 bumped into a number of points, together with a software program downside that prevented it from having the ability to safely dock to the ISS. The second Orbital Take a look at Flight (OFT-2) was delayed a 12 months on account of a corrosion downside in a number of the propulsion system valves.
Groups have been optimistic a few 2023 launch of the CFT mission, however the mission was delayed till 2024 as they labored by questions in regards to the parachutes’ delicate hyperlinks and both mitigated or eliminated a few mile of flammable tape inside the spacecraft.