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Boeing’s Starliner mission will attempt its third crewed flight test on Wednesday, a milestone a decade in the making.
The new spacecraft’s maiden voyage with humans aboard is on track for liftoff atop an Atlas V rocket at 10:52 a.m. ET from Cape Canaveral Space Force Station in Florida.
The historic event will be streamed live on NASA’s website beginning at 6:45 a.m. ET.
Veteran NASA astronauts Butch Wilmore and Suni Williams are about to board the Starliner capsule for a journey that will take them to the International Space Station.
Weather conditions are 90% favorable for Wednesday morning’s launch, with cumulus clouds the only concern, according to the US Space Force’s 45th Weather Squadron. If the liftoff doesn’t happen on Wednesday, there is another opportunity on Thursday at 10:29 a.m. ET, according to NASA.
The mission, known as the Crew Flight Test, is the culmination of Boeing’s efforts to develop a spacecraft to rival SpaceX’s prolific Crew Dragon capsule and expand the United States’ ability to carry astronauts to the space station as part of NASA’s commercial crew program. The federal agency’s initiative aims to foster collaboration with private industry partners.
If successful, the flight would mark only the sixth inaugural flight of a crewed spacecraft in U.S. history, NASA Administrator Bill Nelson noted at a press conference in May.
“It started with Mercury, then Gemini, then Apollo, the Space Shuttle, then (SpaceX) Dragon — and now Starliner,” Nelson said.
Williams will also make history as the first woman to fly aboard such a mission.
Cory S Huston/NASA
NASA astronauts Butch Wilmore (left) and Suni Williams have been quarantined since late April to protect their health.
If the Starliner successfully lifts off, the astronauts will spend just over 24 hours en route to the space station.
After landing Thursday around 12:15 p.m. ET, Williams and Wilmore are scheduled to spend eight days living in the orbiting lab, joining the seven astronauts and cosmonauts already aboard.
Aboard the Starliner is a key pump needed to repair the space station’s urine processor assembly that failed on May 29.
“This urine processor takes all of the crew’s urine and processes it in the first step of the water recovery system,” said Dana Weigel, NASA’s International Space Station program manager. “Then it sends it downstream to a water processor that turns it into potable water. The station is really designed as a closed loop.”
Now the urine must be stored on board in containers, so the Starliner’s expected arrival at the space station cannot come soon enough.
The astronauts will test various aspects of the Starliner’s capabilities, including the performance of the spacecraft’s thrusters, the functioning of their spacesuits in the capsule, and manual piloting in case the crew needs to override the spacecraft’s autopilot.
Williams and Wilmore will also test the Starliner’s “safe haven” capability, which is designed to offer the space station crew shelter in the event of a problem, Steve Stich, NASA’s commercial crew program manager, said during a May 31 news conference.
When it’s time to head home, the astronauts will return using the same Starliner capsule and parachute to land at one of several designated locations in the southwestern United States.
Years of stalled development, test flight problems and other costly setbacks slowed the Starliner’s journey to the launch pad. Meanwhile, Boeing’s competitor in NASA’s Commercial Crew program — SpaceX — has become a transportation provider for the space agency’s astronauts.
The mission could be the last major milestone before NASA finds the Boeing Starliner spacecraft ready for routine operations carrying astronauts and cargo to the space station.
A series of problems caused previous crewed launch attempts, on May 6 and June 1, to be scrapped.
Two hours before the May 6 launch attempt, engineers identified a problem with a valve on the second stage, or upper part, of the Atlas V rocket, built by United Launch Alliance, a joint venture between Boeing and Lockheed Martin. The entire stack, including rocket and spacecraft, was rolled back from the launch pad for testing and repairs.
The teams also worked on a small helium leak in the spacecraft’s service module, a “structural vulnerability” in the propulsion system, and assessed parachutes for the Starliner capsule.
Starliner was just 3 minutes and 50 seconds from liftoff Saturday afternoon when an automatic shutdown was triggered by the ground-based launch sequencer, or computer, that launches the rocket.
Over the weekend, United Launch Alliance technicians and engineers assessed ground support equipment and examined three large computers housed in a housing at the base of the launch pad. Each computer is identical and provides triple redundancy to ensure the safe launch of manned missions.
“Imagine a big rack that’s a big computer, where the functions of the computer, like the controller, are separated out into individual cards or circuit boards,” said Tory Bruno, president and CEO of United Launch Alliance, during a press conference Saturday. . “They are all separate, but together they form an integrated controller.”
The cards in the computers are responsible for various key systems that must occur before launch, such as loosening the screws at the base of the rocket so that it can lift off after ignition.
During the last four minutes before the start, all three computers must communicate with each other and agree. But during Saturday’s countdown, the card on one of the computers was responding six seconds slower than the other two computers, which Bruno said signaled something was wrong and triggered an automatic suspension.
Over the weekend, engineers evaluated the computers, their power supply and the network communication between the computers. The team isolated the problem to a single ground power supply in one of the computers that powers the computer cards responsible for key countdown events — including the rocket’s upper stage replenishment valves, which also caused the problem during the countdown, according to an update shared by NASA.
The Starliner teams reported no signs of physical damage to the computer, which they removed and replaced with a spare. Other computers and their cards have also been assessed and according to the ULA team, they are all working normally as expected.