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Boeing’s Starliner mission will make its third attempt at its first crewed flight test on Wednesday in a decade a decade in the making.
The new manned spacecraft’s maiden voyage is on track to take off atop an Atlas V rocket at 10:52 am from the Cape Canaveral Space Force Station in Florida.
The historic event will be broadcast 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 for 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 US Space Force’s 45th Weather Squadron. If liftoff doesn’t happen on Wednesday, there’s another chance at 10:29 a.m. ET Thursday, according to NASA.
The mission, known as the Crew Flight Test, is the culmination of Boeing’s efforts to develop a spacecraft to compete with SpaceX’s prolific Crew Dragon capsule and expand the United States’ options for ferrying 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 only the sixth inaugural flight of a crewed spacecraft in US history, NASA Administrator Bill Nelson noted in 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 aboard such a mission.
High goals are a historic flight
If Starliner succeeds in liftoff, the astronauts will spend just over 24 hours traveling to the space station.
After taking off around 12:15 pm ET Thursday, Williams and Wilmore are set to spend eight days living in the orbiting laboratory, joining the seven astronauts and cosmonauts already on board.
Aboard Starliner is a critical 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 in the first stage 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 that turns it into drinking water. The station is really designed to be a closed loop.”
Now, the urine must be stored on board in containers, so it cannot arrive at the space station which is expected to be Starliner soon enough.
The astronauts will test various aspects of Starliner’s capabilities, including the performance of the spacecraft’s thruster, how their spacesuits function inside the cavity, and manual piloting in case the crew needs to override the spacecraft’s autopilot.
Williams and Wilmore will also test Starliner’s “safe haven” capability, which is designed to offer shelter to the space station crew if there is a problem, according to Steve Stich, manager of NASA’s Commercial Crew Program, during a May 31 news conference. .
When it’s time to go home, the astronauts will return using the same Starliner capsule and parachute to land at one of several designated sites throughout the southwestern United States.
With years of development, test flight problems and other costly obstacles, Starliner’s path to the launch pad has been delayed. Meanwhile, Boeing’s competitor under NASA’s Commercial Crew program – SpaceX – is a transportation provider for the space agency’s astronauts.
This mission could be the last major milestone before NASA deems the Boeing Starliner spacecraft ready for routine operations to deliver astronauts and cargo to the space station.
Weeks of troubleshooting
Several issues caused the previous crewed launch attempts, on May 6 and June 1, to be scrapped.
Two hours before the launch attempt on May 6, 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 rolled back from the pad for testing and repairs.
Teams also worked through a small helium leak inside the spacecraft service module, a “design vulnerability” in the propulsion system and evaluated the parachutes for the Starliner capsule.
Starliner was just 3 minutes and 50 seconds from liftoff Saturday afternoon, when the ground launch sequencer, or the computer that launched the rocket, triggered an automatic hold.
United Launch Alliance technicians and engineers assessed the ground support equipment over the weekend, examining three large computers housed inside a shelter at the base of the launch pad. All computers are identical, providing triple redundancy to ensure the safe launch of crewed missions.
“Imagine a big rack is a big computer where the functions of the computer as a controller are broken up separately into individual cards or printed circuit boards,” said Tory Bruno, president and CEO of United Launch Alliance, during a news conference Saturday. . “They’re all independent, but together, it’s an integrated controller.”
The cards inside the computers are responsible for various key systems that must be in place before launch, such as loosening bolts at the bottom of the rocket so that it can be lifted after ignition.
During the last four minutes before the launch, the 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, which indicated something wasn’t right and prompted its automatic hold, according to Bruno.
Over the weekend, engineers assessed the computers, their power supply and network communication between the computers. The team isolated the issue to a single ground power supply within one of the computers, which supplies power to the computer cards responsible for key countdown events – including the replenishment valves for the rocket’s upper stage, which ‘an issue also arose 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 performing normally as expected, according to the ULA team.
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