Watch the historic launch of Boeing’s first manned Starliner mission

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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 a decade in the making.

The new spacecraft’s maiden voyage with humans on board is on track to lift off atop an Atlas V rocket at 10:52 a.m. ET from Cape Canaveral Space Force Station in Florida.

The historic event will be broadcast live on NASA websitewith coverage beginning at 6:45 a.m. ET.

Veteran NASA astronauts Butch Wilmore and Suni Williams are ready to travel 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, according to the U.S. Space Force’s 45th Weather Squadron. If liftoff does not occur on Wednesday, there will be another opportunity at 10:29 a.m. ET on Thursday, according to NASA.

The mission, known as the Crew Flight Test, is the culmination of Boeing’s efforts to develop a spacecraft that rivals SpaceX’s prolific Crew Dragon capsule and expands the United States’ options for transporting astronauts to the space station under the Crew Program. NASA commercial. The federal agency’s initiative aims to promote collaboration with private industry partners.

If successful, the flight would mark just the sixth maiden voyage of a manned 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’s) Dragon — and now Starliner,” Nelson said.

Williams will also make history as the first woman to fly aboard such a mission.

Historic flight has lofty goals

If the Starliner lifts off successfully, astronauts will spend just over 24 hours traveling to the space station.

After docking around 12:15 pm ET on Thursday, Williams and Wilmore will spend eight days living in the orbiting laboratory, joining the seven astronauts and cosmonauts already on board.

Aboard Starliner is a crucial pump needed to repair the space station’s urine processor assembly, which failed on May 29.

“This urine processor takes all of the crew’s urine and processes it in the first step of a water recovery system,” said Dana Weigel, NASA’s International Space Station Program Manager. “It then sends it downstream to a water processor that turns it into drinking water. The station was really designed to be a closed circuit.”

Now, urine has to be stored onboard in containers, so the Starliner’s early arrival at the space station can’t happen soon enough.

Astronauts will test several aspects of Starliner’s capabilities, including the performance of the spacecraft’s thruster, how their spacesuits work inside the capsule, and manual piloting should the crew need to override the spacecraft’s autopilot.

Williams and Wilmore will also test Starliner’s “safe harbor” capability, designed to provide shelter to the space station crew if there is any trouble, according to Steve Stich, manager of NASA’s Commercial Crew Program, during a press conference on March 31. of May.

When it’s time to return 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 development interruptions, test flight problems and other costly setbacks have slowed Starliner’s path to the launch pad. Meanwhile, Boeing’s competitor in NASA’s Commercial Crew program – SpaceX – has become the primary provider of transportation for the space agency’s astronauts.

This mission could be the final major milestone before NASA considers Boeing’s Starliner spacecraft ready for routine operations to deliver astronauts and cargo to the space station.

Troubleshooting weeks

A series of problems meant that previous manned launch attempts, on May 6 and June 1, were scrapped.

Two hours before the launch attempt on May 6, engineers identified a problem with a valve in the second stage, or upper part, of the Atlas V rocket, which was built by United Launch Alliance, a joint venture between Boeing and Boeing. LockheedMartin. The entire stack, including the rocket and spacecraft, was removed 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 the Starliner capsule parachutes.

The Starliner was just 3 minutes and 50 seconds from takeoff on Saturday afternoon when a automatic hold has been triggered by the ground launch sequencer or by the 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 the same, 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 divided separately into individual boards or printed circuit boards,” said Tory Bruno, president and CEO of United Launch Alliance, during a press conference on Saturday. . “They are all independent, but together they form an integrated controller.”

Cards inside computers are responsible for different key systems that must occur before launch, such as releasing screws on the base of the rocket so it can take off after ignition.

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 in responding than the other two computers, indicating something was not correct and triggering an automatic hold, according to Bruno.

Over the weekend, engineers evaluated the computers, their power supply, and network communications between the computers. The team isolated the problem to a single terrestrial power supply inside one of the computers, which supplies power to the computer boards responsible for the main countdown events – including the refueling valves for the rocket’s upper stage, which also caused an issue during the countdown, 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. The other computers and their boards were also evaluated and all are functioning normally as expected, according to the ULA team.

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