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Boeing’s Starliner mission will make a third attempt to launch its first crewed flight test on Wednesday, a milestone that has been a decade in the making.
The new spacecraft’s maiden voyage with humans on board is set to lift off atop an Atlas V rocket at 10:52 a.m. ET from the Cape Canaveral space 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 expected to board the Starliner capsule for a journey that will take them to the International Space Station.
Weather conditions are 90% favorable for a launch Wednesday morning, with the only concern being cumulus clouds, according to the 45th Weather Squadron of the US Space Force. If liftoff does not occur on Wednesday, there will be 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 capable of rivaling SpaceX’s prolific Crew Dragon capsule and expanding the United States’ options for carrying astronauts to the space station as part of NASA’s Commercial Crew Program. The federal agency’s initiative aims to promote collaboration with private industry partners.
If successful, the flight would mark only the sixth maiden voyage of a crewed spacecraft in U.S. history, NASA Administrator Bill Nelson said 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 participate in such a mission.
If Starliner launches successfully, astronauts will spend just over 24 hours traveling to the space station.
After docking around 12:15 p.m. ET on Thursday, Williams and Wilmore are expected to spend eight days in the orbiting laboratory, joining the seven astronauts and cosmonauts already on board.
On board the Starliner is a crucial pump needed to repair the space station’s urine processing assembly, which failed on May 29.
“This urine processor takes all of the crew’s urine and processes it in the first stage of a water reclamation system,” said Dana Weigel, International Space Station program manager for the NASA. “It then sends it downstream to a water transformer which turns it into drinking water. The resort is truly designed to be a closed loop.
Now urine must be stored onboard in containers, so Starliner’s planned 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 thruster, the operation 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 Starliner’s “shelter” capability, designed to provide shelter for the space station crew in the event of a problem, according to Steve Stich, manager of NASA’s commercial crew program, during the a press conference on May 31.
When it is time to return home, the astronauts will return using the same Starliner capsule and parachute to land in one of several designated locations in the southwest United States.
Years of development delays, 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 go-to transportation provider for the space agency’s astronauts.
The mission could be the last major step before NASA considers Boeing’s Starliner spacecraft ready for routine operations to deliver astronauts and cargo to the space station.
A number of problems led to the failure of previous crewed launch attempts on May 6 and June 1.
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 the rocket and spacecraft, was removed from the launch pad for testing and repair.
Teams also worked on a small helium leak in the spacecraft’s service module, a “design vulnerability” in the propulsion system and evaluated the Starliner capsule’s parachutes.
Starliner was just 3 minutes and 50 seconds from liftoff Saturday afternoon, when an automatic hold was triggered by the ground launch sequencer, or the computer that launches the rocket.
United Launch Alliance technicians and engineers evaluated ground support equipment over the weekend, examining three large computers housed in a shelter at the base of the launch pad. Each computer is identical, providing triple redundancy to ensure the safe launch of crewed missions.
“Imagine a large rack that is a large computer in which the functions of the computer as a controller are divided separately into individual boards or circuit boards,” said Tory Bruno, president and CEO of United Launch Alliance, during a press conference on Saturday. . “They are all self-contained, but together they form an integrated controller. »
The boards inside the computers are responsible for different key systems that must be activated before a launch, such as loosening bolts at the base of the rocket so it can take off after ignition.
During the last four minutes before launch, the three computers must communicate and hear each other. But during Saturday’s countdown, a card on one of the computers reacted six seconds slower than the other two computers, indicating something was wrong 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 ground power supply in one of the computers, which powers computer boards responsible for key countdown events, including the rocket’s upper stage resupply valves, 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 cards were also evaluated, and all are functioning normally as expected, according to the ULA team.