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Boeing’s Starliner mission will make a third attempt Wednesday to launch its first crewed flight test, a milestone a decade in the making.
The new spacecraft’s maiden voyage with humans on board is on schedule to lift off atop an Atlas V rocket from the Cape Canaveral Space Force Station in Florida at 10:52 a.m. ET.
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 will ride aboard the Starliner capsule on a journey that will take them to the International Space Station.
Weather conditions are 90% favorable for a Wednesday morning launch, with the only concern being cumulus clouds, the U.S. Space Force’s 45th Weather Squadron said. If the launch doesn’t happen on Wednesday, there will be another possibility for 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 that can rival SpaceX’s prolific Crew Dragon capsule and expand the United States’ capabilities for transporting astronauts to is expanding the space station under NASA’s Commercial Crew Program. The federal agency’s initiative aims to promote collaboration with private sector partners.
If successful, the flight would mark just the sixth inaugural voyage of a manned spacecraft in U.S. history, NASA Administrator Bill Nelson noted at a news conference in May.
“It started with Mercury, then Gemini, then Apollo, the 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.
Historic flights have lofty goals
If Starliner lifts off successfully, the astronauts will travel to the space station in just over 24 hours.
After docking around 12:15 p.m. ET on Thursday, Williams and Wilmore will spend eight days in the orbiting laboratory, where they will join the seven astronauts and cosmonauts already on board.
On board Starliner is a crucial pump needed to repair the space station’s urine processor, which failed on May 29.
“That urine processor takes all the crew’s urine and processes it in the first step of a water recovery system,” said Dana Weigel, manager of NASA’s International Space Station Program. “It is then sent downstream to a water processor, which turns it into drinking water. The station is really designed as a closed loop.”
Now the urine must be stored in containers on board, so Starliner’s expected arrival at the space station can’t come soon enough.
The astronauts will test various aspects of Starliner’s capabilities, including the performance of the spacecraft’s thrusters, how their spacesuits function in the capsule and manual controls in case the crew needs to override the spacecraft’s autopilot.
Williams and Wilmore will also test Starliner’s “safe harbor” capability, designed to provide shelter for the space station’s crew if there is a problem, said Steve Stich, manager of NASA’s Commercial Crew Program, during a May 31 news conference .
When it’s time to go home, the astronauts return using the same Starliner capsule and parachute to land at one of several designated locations in the southwestern United States.
Years of development problems, test flight problems and other costly setbacks have slowed Starliner’s path to the launch pad. Meanwhile, Boeing’s competitor under NASA’s Commercial Crew program – SpaceX – has become the transportation provider for the space agency’s 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.
Weeks of troubleshooting
A number of problems caused the previous crewed launch attempts, on May 6 and June 1, to be canceled.
Two hours prior to the May 6 launch attempt, engineers discovered a problem with a valve on the second stage, or upper portion, of the Atlas V rocket, which was built by United Launch Alliance, a joint venture between Boeing and Lockheed Martin. The entire stack, including the rocket and spacecraft, was rolled back from the launch pad for testing and repairs.
Teams also worked on a small helium leak in the spacecraft’s service module, a “design vulnerability” in the propulsion system and assessed the parachutes for the Starliner capsule.
Starliner was just 3 minutes and 50 seconds away from liftoff Saturday afternoon when an automatic stop was activated by the ground launch sequencer, or computer that launches the rocket.
Technicians and engineers from United Launch Alliance this weekend assessed ground support equipment and examined three large computers housed in a shelter at the base of the launch pad. Each computer is the same and provides triple redundancy to ensure the safe launch of manned missions.
“Imagine a large rack that is a large computer, where the functions of the computer as a controller are separated into individual cards or circuit boards,” said Tory Bruno, president and CEO of United Launch Alliance, during a press conference on Saturday. . “They all stand alone, but together they form an integrated controller.”
The cards in the computers are responsible for several key systems that must occur before a launch, such as loosening bolts at the base of the rocket so that it can take off after ignition.
During the last four minutes before launch, all three computers must communicate with each other and reach an agreement. But during the countdown on Saturday, a card on one of the computers responded six seconds slower than the other two computers, indicating something was wrong and causing an automatic lockout, according to Bruno.
Over the weekend, engineers evaluated the computers, their power supply and the network communications between the computers. The team isolated the problem to a single ground power supply within one of the computers, which provides power to the computer boards responsible for the key countdown events – including the replenishment valves for the rocket’s upper stage, which also caused a problem during the countdown, according to to an update shared by NASA.
Starliner teams reported no signs of physical damage to the computer, which they removed and replaced with a spare computer. The other computers and their maps were also assessed and according to the ULA team, they are all functioning normally as expected.
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