After pondering the totality of issues that arose during a December test flight of Boeing’s Starliner spacecraft this week, NASA chief of human spaceflight Doug Loverro said Friday that he decided to escalate the incident.
So he designated Starliner’s uncrewed mission, during which the spacecraft flew a shortened profile and did not attempt to dock with the International Space Station, as a “high visibility close call.” This relatively rare designation for NASA’s human spaceflight program falls short of “loss of mission” but is nonetheless fairly rare. It was last used by NASA after a spacewalk in 2013 when water began to dangerously pool in the helmet of astronaut Luca Parmitano.
Asked to explain during a conference call with reporters why he did this, Loverro said, “We could have lost a spacecraft twice during this mission.”
In this, Loverro referred to two software errors that occurred during the two-day flight. The first problem occurred when Starliner captured the wrong “mission elapsed time” from its Atlas V launch vehicle—it was supposed to pick up this time during the terminal phase of the countdown, but instead it grabbed data 11 hours off of the correct time. This led to a delayed push to reach orbit. The second error, caught and fixed just a few hours before the vehicle returned to Earth through the atmosphere, was due to a software mapping error that would have caused thrusters on Starliner’s service module to fire in the wrong manner.
NASA and Boeing officials held Friday’s teleconference to announce the conclusion of a report from an Independent Review Team established after December’s flight. These reviewers made 60 recommendations to NASA and Boeing for corrective actions that ranged from fixing these software issues to ferreting out others that may still exist in the spacecraft’s flight code. The investigative team is also still looking into an issue that led to multiple dropouts in communications between the ground and spacecraft during key moments of the flight.
Corrective action plan
By declaring the Starliner mishap a “close call,” Loverro also formally opened a process during which the space agency’s Safety Office will investigate the organization elements that may have led to the incident—likely focusing on why NASA did not detect the errors in Starliner’s flight software.
Loverro said no decisions are close to being made on when Starliner will return to flight or whether Boeing will have to fly another uncrewed demonstration test flight before NASA astronauts fly on Starliner. The next step, he said, is for Boeing to prepare a “corrective action plan” to implement the review team’s findings, and that will include a schedule. NASA will evaluate that plan and then it may be in a position to decide whether another test flight is needed.