ORLANDO, Fla. — Two coding errors that went undetected by the teams at Boeing could have led to the collision of two spacecraft during a test of Boeing’s astronaut capsule in December, officials said Friday.
The software issues were representative of multiple failures at various levels in Boeing and NASA’s testing and verification processes. And they didn’t come to light until the capsule, called the CST-100 Starliner, launched on Dec. 20 from the Space Coast on a test mission to the International Space Station with no astronauts aboard.
Shortly into the flight, the capsule failed to reach its correct orbit because, the teams later learned, the vehicle’s internal timing system was running on an 11-hour delay, meaning it didn’t perform critical maneuvers when it was supposed to. Officials then made the decision to land the capsule back on Earth instead of continue on in the mission.
But before they could do that, Boeing went “hunting” for similar software problems —and found another one.
A software issue was located in the thrusters that move what’s known as the service module away from the crew module before the capsule returns to Earth. If the wrong thrusters fired, the service module could have collided with the crew module, damaging it or sending it off course.
“Nothing good can come from those two spacecraft bumping,” said Jim Chilton, senior vice president of Boeing Space and Launch, during a press call Friday afternoon.
The conference call came following a meeting of NASA’s Aerospace Safety Advisory Panel Thursday, where the service module issue was first revealed to the public.
At the time of the flight, Boeing was able to catch the problem and correct the code with just about two hours to spare before the capsule returned to Earth the morning of Dec. 22.
Those two issues, plus another communication problem that Boeing and NASA are still further investigating, have been the sources of an independent review that is now calling for a complete reassessment of Boeing’s safety systems.
Boeing will also go back and reverify its entire flight software —about a million lines of code.
Douglas Loverro, associate administrator for NASA’s Human Exploration and Operations Mission Directorate, said there were perhaps three or four instances in the review process where the incorrect code should have been caught.
“The process broke down in many areas in each of those things,” Loverro said, adding that NASA’s oversight was also “insufficient.”
Challenges communicating with the spacecraft from Earth also made it more difficult to fix the problems as they were happening. Boeing suspects that noise from cell phone towers in the area made it challenging to get signals to the Starliner when it became clear there was an issue.
Still, NASA and Boeing are not yet committing to performing a second test flight without humans. The full investigation into the issues is expected to be completed at the end of the month, at which point officials say they will reassess the next step in the program.
If all had gone well, Boeing was next scheduled to perform a test mission with humans on board.
The software issues are the latest problems in a string of setbacks for NASA’s Commercial Crew Program, which was designed to return to the United States the capability of launching American astronauts to the ISS from U.S. soil instead of Russian soil, as NASA has been doing since 2011 when the space shuttle program ended.
Boeing was initially awarded $4.2 billion to perform the feat, while SpaceX, the other Commercial Crew provider, got $2.6 billion.
SpaceX already performed the mission Boeing attempted in December successfully without major issues. But Elon Musk’s rocket company hasn’t gone through development of its capsule, Crew Dragon, unscathed, either. In April, SpaceX’s astronaut capsule exploded during testing of its abort engines. In June 2018, Boeing’s Starliner experienced a fire during a test of its abort engines, too.
NASA originally planned to start ferrying astronauts to the space station in 2017, but challenges in the program have delayed it now more than two years. It’s unclear whether Boeing will launch Starliner again this year. SpaceX is on track to launch with humans sometime in 2020.
NASA Administrator Jim Bridenstine emphasized that it was “unusual” for NASA to offer an update on an investigation that is still underway, but Bridenstine said the agency was committed to transparency regarding the taxpayer-funded Commercial Crew Program.
Speaking to NASA leadership ahead of Friday’s call, Bridenstine said he directed them to “never ever be afraid of the truth.”