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Boeing’s Starliner mission will make a third attempt to launch its first crewed flight test on Wednesday in a milestone that has been a decade in the making.
The new spacecraft’s maiden voyage with humans aboard is on track to lift off atop an Atlas V rocket at 10:52 a.m. ET from the Cape Canaveral Space Force Station in Florida.
The historic event will be streamed live on NASA’s website, with coverage beginning at 6:45 a.m. ET.
Veteran NASA astronauts Butch Wilmore and Suni Williams are set to board the Starliner capsule on a journey that takes them to the International Space Station.
Weather conditions are 90% favorable for a Wednesday morning launch, with the only concern being cumulus clouds, according to the US Air Force’s 45th Weather Squadron. If liftoff doesn’t happen Wednesday, there’s another chance at 10:29 a.m. Thursday, 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’ options for transporting astronauts to the space station under NASA’s Commercial Crew Program. The federal agency’s initiative aims to foster collaboration with private industry partners.
If successful, the flight would mark just the sixth inaugural flight of a crewed spacecraft in US history, NASA Administrator Bill Nelson noted at a press conference in May.
“It started with Mercury, then Gemini, then Apollo, Space Shuttle, then (SpaceX’s) Dragon — and now Starliner,” Nelson said.
Williams will also make history as the first woman to fly such a mission.
Cory S Huston/NASA
NASA astronauts Butch Wilmore (left) and Suni Williams have been in quarantine to protect their health since late April.
If Starliner successfully lifts off, astronauts will spend just over 24 hours traveling to the space station.
After docking around 12:15 p.m. Thursday, Williams and Wilmore will spend eight days living in the orbiting lab, joining the seven astronauts and cosmonauts already aboard.
On board the Starliner is a core pump needed to fix the space station’s urine processor assembly, which failed on May 29.
“That urine processor takes all of the crew’s urine and processes it into the first step of a water recovery system,” said Dana Weigel, manager for NASA’s International Space Station Program. “It then sends it downstream to a water processor which turns it into drinking water. The station is really designed to be a closed loop.”
Now, urine must be stored onboard in containers, so the Starliner’s anticipated arrival at the space station can’t come soon enough.
Astronauts will test various aspects of Starliner’s capabilities, including the performance of the shuttle’s thrusters, how their spacesuits work inside the capsule, and manual piloting in case the crew needs to override the shuttle’s autopilot.
Williams and Wilmore will also test the Starliner’s “safe haven” capability, designed to give the space station crew a shelter if there’s a problem, according to Steve Stich, manager of NASA’s Commercial Crew Program, during a press conference on May 31.
When it’s time to head home, the astronauts will return using the same Starliner capsule and parachute to a landing at one of several designated locations throughout the southwestern United States.
Years of development disruptions, test flight problems and other costly setbacks have slowed the Starliner’s path to the launch pad. Meanwhile, Boeing’s competitor under NASA’s Commercial Crew program — SpaceX — has become the space agency’s primary transportation provider for astronauts.
This mission could be the last major milestone before NASA deems Boeing’s Starliner spacecraft ready for routine operations to deliver astronauts and cargo to the space station.
A number of problems caused earlier 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 in the second stage, or upper section, of the Atlas V rocket, which was built by United Launch Alliance, a joint venture between Boeing and Lockheed Martin. . The entire assembly, including the rocket and spacecraft, was withdrawn from the launch pad for testing and repairs.
The teams also worked through a small helium leak inside the spacecraft’s service module, a “design vulnerability” in the propulsion system, and evaluated parachutes for the Starliner capsule.
Starliner was just 3 minutes and 50 seconds from liftoff Saturday afternoon when an automatic hold was triggered by the ground launch sequence, or computer that launches the rocket.
United Launch Alliance technicians and engineers evaluated ground support equipment over the weekend, examining three large computers housed inside a shelter at the base of the launch pad. Each computer is identical, providing triple redundancy to ensure the safe launch of manned missions.
“Imagine a big rack that is a big computer where the functions of the computer as a controller are separated separately on individual cards or printed circuit boards,” said Tory Bruno, president and CEO of United Launch Alliance, during a press conference on Saturday. . “They’re all independent, but together, it’s an integrated controller.”
Cards inside the computers are responsible for various key systems that must occur before launch, such as loosening bolts on the base of the rocket so it can be removed after launch.
During the last four minutes before launch, all three computers must communicate and agree with each other. But during Saturday’s countdown, a card on one of the computers was six seconds slower to respond than the other two computers, indicating something was wrong and triggering an automatic hold, according to Bruno.
Over the weekend, engineers evaluated computers, power supplies, and network communication between computers. According to an update shared by NASA.
Starliner crews reported no signs of physical damage to the computer, which they removed and replaced with a spare. Other computers and their cards were also evaluated, and all of them are functioning normally as expected, according to the ULA team.