Boeing's Starliner prepares for its third launch try following weekend delay

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The latest attempt at an inaugural crewed launch of Boeing’s Starliner spacecraft is set for Wednesday following a computer issue that caused a delay just before liftoff on Saturday.

The historic mission, known as the Crew Flight Test, is scheduled to launch at 10:52 a.m. ET from Cape Canaveral Space Force Station in Florida. You can watch the event live on NASA’s website, starting at 6:45 a.m. ET.

Leading the mission are experienced NASA astronauts Butch Wilmore and Suni Williams, who will be the first crew to travel aboard Starliner. They will be propelled into orbit by an Atlas V rocket, which is a creation of United Launch Alliance, a collaboration between Boeing and Lockheed Martin.

The long-awaited flight took off on Saturday afternoon but was halted 3 minutes and 50 seconds after liftoff. The ground launch sequencer, the computer responsible for launching the rocket, automatically triggered a hold. The astronauts were safely taken out of the capsule, and Williams and Wilmore went back to crew quarters while the rocket's fuel was drained.

Boeing's Starliner spacecraft sits atop a United Launch Alliance Atlas V rocket at Cape Canaveral Space Force Station in Florida on May 31.

Boeing's Starliner spacecraft sits atop a United Launch Alliance Atlas V rocket at Cape Canaveral Space Force Station in Florida on May 31.

Joe Raedle/Getty Images

United Launch Alliance technicians and engineers spent the weekend evaluating the ground support equipment. They focused on three large computers located inside a shelter at the base of the launchpad. These computers are identical, providing triple redundancy to ensure the safe launch of crewed missions.

During a news conference on Saturday, Tory Bruno, the president and CEO of United Launch Alliance, explained the setup. He likened it to a large rack serving as a big computer, where the functions are divided into separate cards or printed wire circuit boards. These components work independently but are integrated to function as a controller.

The cards inside the computers handle important tasks needed for a successful launch, like releasing bolts at the base of the rocket to allow it to lift off once ignited.

In the last four minutes before liftoff, all three computers need to communicate and be in sync. However, during Saturday's countdown, one of the computer cards was slower by six seconds compared to the others. This discrepancy signaled a problem and automatically paused the launch, as explained by Bruno.

Over the weekend, engineers examined the computers, their power source, and the network connections between them. The problem was traced back to a single ground power supply in one of the computers. This power supply is crucial for key countdown events, such as controlling the replenishment valves for the rocket’s upper stage, as reported by NASA.

The Starliner teams did not find any physical damage to the computer. They decided to remove the faulty power supply and replace it with a spare one. In the meantime, mission specialists are working on analyzing the defective power unit to figure out what caused the issue.

The other computers and their cards were also assessed, and all of them are performing normally as expected, according to the ULA team.

The next attempt

Mission teams had successfully addressed several issues that arose before Saturday's launch attempt. One of the problems involved a loss of data from ground valves that refuel the second stage of the Atlas V rocket with liquid oxygen and hydrogen.

The liquid oxygen and hydrogen are essential fuels for the rocket, but they tend to evaporate while the rocket is on the launch pad. To ensure an adequate fuel supply, the valves need to continuously replenish the rocket until liftoff. After careful assessment, the mission teams managed to switch to a backup system for the valve data and were able to continue with the refueling process.

Weather conditions are looking good for a Wednesday morning launch, with a 90% chance of favorable conditions. The only thing to watch out for is cumulus clouds, according to the US Space Force’s 45th Weather Squadron. If the launch doesn't happen on Wednesday, there's another chance at 10:29 a.m. ET on Thursday, as per NASA's schedule.

If all goes well and Starliner takes off successfully, the astronauts will spend a little over 24 hours traveling to the International Space Station.

Veteran NASA astronauts Butch Wilmore (left) and Suni Williams are seen on Saturday prior to Starliner's second launch attempt.

Veteran NASA astronauts Butch Wilmore (left) and Suni Williams are seen on Saturday prior to Starliner's second launch attempt.

After docking at the orbiting laboratory, Williams and Wilmore will spend eight days there with seven other astronauts and cosmonauts. They will be testing the Starliner spacecraft while it's docked at the space station. Afterwards, they will return home using the same capsule, landing via parachute in one of several locations across the southwestern United States.

In the meantime, the two astronauts remain in quarantine to protect their health ahead of launch, and they are practicing procedures and simulations ahead of the historic flight, according to NASA.

Editor's P/S:

The impending inaugural crewed launch of Boeing's Starliner spacecraft is a testament to the resilience and ingenuity of the aerospace industry. Despite a technical setback that caused a delay in the original launch attempt, engineers and technicians have worked tirelessly to resolve the issue and ensure a safe and successful mission. The upcoming launch represents a significant milestone in the development of commercial spaceflight and will pave the way for more frequent and affordable access to space.

The mission, led by experienced NASA astronauts Butch Wilmore and Suni Williams, will test the Starliner spacecraft's capabilities and pave the way for future crewed missions to the International Space Station and beyond. The spacecraft's ability to dock with the space station and sustain a crew for an extended period will demonstrate its reliability and potential for future missions. The successful completion of this mission will not only boost the confidence in commercial spaceflight but also open up new possibilities for scientific research, exploration, and international collaboration in space.