Nearly two and a half years after its initial launch didn’t go according to plan, Boeing’s new passenger spacecraft, the CST-100 Starliner, was successfully launched into space this afternoon, reaching the proper orbit needed to rendezvous with the International Space Station ISS tomorrow night. The successful launch marks the beginning of a pivotal test flight for Starliner that will take place in space over the next week, one that will help demonstrate whether the capsule can one day carry humans into space.
Starliner is a private spacecraft developed by Boeing in partnership with NASA primarily to transport the agency’s astronauts to and from the International Space Station in low Earth orbit. The capsule is one of two vehicles, along with SpaceX’s Crew Dragon, that NASA helped fund to shift space transportation from government to commercial companies. But before NASA’s astronauts can pilot the Starliner, the space agency wants Boeing to demonstrate that the capsule can perform all the tasks of normal spaceflight without a crew on board.
That’s what today’s flight is designed for, but it was a bumpy road to get to this point. In fact, this mission is a repeat. Boeing attempted the same unmanned Starliner flight in December 2019, but that mission, dubbed OFT, ran into a series of software issues. The capsule never made it to the International Space Station, and Boeing had to get Starliner home early because it couldn’t demonstrate its ability to dock with the ISS. Boeing agreed to re-run the flight for NASA, coming close to launch last summer. But just hours before launch, Boeing halted the flight after discovering some propellant valves that were malfunctioning. The company had to bring Starliner back to the factory to address the problem.
Now Starliner is finally in orbit where it should be. “We have good orbital insert combustion,” said Josh Barrett, a communications representative for Boeing, during the launch livestream. “Starliner is in stable, circular orbit en route to the International Space Station.”
But it still has a lot to prove. It then needs to show that it can automatically dock with the International Space Station, using the onboard sensors to direct itself to an open docking port. After that, it should disconnect and come home, landing safely back on Earth. So while Starliner has achieved success today, the work has only just begun.
Still, Boeing has shown that it has seemingly overcome the difficulties it experienced in 2019. Perhaps the biggest nail-biting moment today came about 31 minutes after launch, when Starliner burned a series of onboard engines to launch itself into its final orbit. Starliner launches into space atop an Atlas V rocket operated by the United Launch Alliance, but its job isn’t done when it detaches from the booster. Four thrusters on Starliner need less than a minute to burn to get the pod into orbit. During the 2019 flight, a software glitch made Starliner think it was the wrong time of day, causing the capsule to misfire its thrusters. As a result, Starliner consumed too much propellant and did not enter the proper orbit needed to reach the ISS.
Today, the thruster firing initially appeared to be going well, and Starliner is in its intended orbit. After the flight, however, Boeing revealed that two thrusters actually failed during orbital insertion, causing them to shut down earlier than intended. The first stopped after a second and the flight control system was diverted to a second bow thruster nearby. However, it also stopped after only 25 seconds and the system had to be diverted to a third bow thruster, which worked as intended. All in all, it didn’t affect Starliner’s ability to reach its planned orbit. Boeing is studying the issue, although the company and NASA claim the failed thrusters would not affect Starliner’s ability to carry out the rest of its mission.
“We’re going to look at the data and try to understand what happened,” Steve Stich, program manager for NASA’s Commercial Crew Program, said at a post-flight press conference. “And then from a redundancy perspective can we restore those thrusters?” Starliner will again use its thrusters to perform burns to adjust its orbit as it approaches the station and also to take the capsule out of orbit on its return to Earth. Ten of the 12 thrusters that Starliner needs, according to Boeing.
Boeing appeared to have no problems with its propellant valves this time, forcing the company to scrub its final launch in August 2021. Before this flight, Boeing replaced the valves and added a sealant to prevent moisture from getting in and causing problems.
Now, Starliner will spend about the next day in space, gradually increasing its orbit, before attempting to dock at the ISS at 7:10 p.m. ET on Friday. Crew members aboard the space station will monitor the capsule’s approach. If successful, they will open the hatch to Starliner on Saturday and pick up some cargo inside. Starliner also rides a mannequin named Rosie the Rocketeer, as well as sensors that help collect data to determine what the flight will be like for future passengers. After docking at the ISS for four to five days, Starliner will detach and then return home, landing somewhere on Earth at one of five possible locations — including White Sands Missile Range in New Mexico.
Depending on how this mission goes, it will be up to NASA and Boeing to prepare Starliner for manned spaceflight and conduct a test mission with people on board called CFT, for Crewed Flight Test. While NASA has selected a group of astronauts to fly on the mission, the agency said it would have the first crew on Starliner by the end of summer.
And there is probably still a long way to go before that can happen. Last week, a NASA security panel noted that the process of certifying the parachutes needed to land Starliner is lagging. In addition, Boeing recently noted that it’s possible the company will redesign the valves that caused problems for the company last year. If that happens, NASA may take longer to certify Starliner for carrying people. And the security panel warned against rushing to do so.
“The panel is pleased that, given all the indications, there is no point in rushing to CFT,” Dave West, a member of NASA’s Aerospace Safety Advisory Panel, said at the meeting. “The opinion that has been consistently expressed to us is that the program will move on to CFT when and only when they are ready.”
The panel also noted that the best way to prepare for CFT was to make this current flight run smoothly. It will be decided next week whether that will happen.
Update May 19, 9:40 PM ET: This story was updated with information from a post-launch press conference detailing an in-flight thruster problem.
SOURCE – www.theverge.com