While NASA attempted to publicly downplay Starliner’s known issues during the early days of the problem-plagued Boeing Crew Test Flight last June, the situation was far more precarious for the astronauts at the controls and the people sitting in mission control. Astronaut Butch Wilmore said that the Boeing Starliner suffered enough thruster failures to lose full control during its launch rendezvous with the International Space Station. The situation should have forced the spacecraft to abort its docking attempt, but NASA apparently waived established flight rules.
The mission’s astronauts had an uneasy feeling that something could go wrong after witnessing thruster failures during the uncrewed Orbital Flight Test missions. However, the initial launch went off without a hitch. The ULA Atlas V rocket maintained its trajectory perfectly and Starliner excelled in its post-separation maneuvering tests. Things changed when Starliner approached the station, however, experiencing thruster failures, and Wilmore took manual control of the spacecraft.
It took a remote reset to regain control of Starliner
Wilmore noted that Starliner had two thrusters fail. If it lost another thruster, the spacecraft would lose control over its six possible movements in a 3D space. Typically, just being on the verge of this loss of control would mandate the crew abort the docking attempt; however, NASA waived its flight rules, and then two more thrusters failed. In an interview with Ars Technica, Wilmore said:
“And this is the part I’m sure you haven’t heard. We lost the fourth thruster. Now we’ve lost 6DOF control. We can’t maneuver forward. I still have control, supposedly, on all the other axes.”
Wilmore didn’t hesitate to call NASA’s Mission Control in Houston heroes for how they managed the crisis. Without forward control, Starliner was in a predicament where it couldn’t dock, but it also couldn’t position itself to reenter the Earth’s atmosphere. Yes, the situation was as dire as it sounds. Mission control instructed Wilmore to let go of the controls so flight controllers could reset the thrusters. The remote override of Starliner’s computer brought back two of the failed thrusters, enough to regain control.
Starliner docked with the ISS, but we know it wasn’t the end. While they were safe onboard the station, they couldn’t pilot the spacecraft home. They could have hitched a ride on one of the other docked vehicles in an emergency, but they were effectively stranded until they could be brought home with one of the ISS’s crew rotation missions. The Starliner would return empty last September, and the crew would return in March – after a nine month stay — with NASA’s SpaceX Crew 9 mission.