Boeing's troubled Starliner mission could have been much worse

A December flight test of Boeing's Starliner may have ended in the loss of the uncrewed spacecraft if major software problems weren't caught during the mission, NASA said Friday.

Why it matters: Boeing is expected to start flying NASA astronauts to the International Space Station on Starliner this year, but the test flight issues could push back Boeing's first crewed flight.

Details: The uncrewed Starliner was expected to dock with the space station after its launch on Dec. 20, but a software issue involving a timer onboard the craft prevented the two from connecting, forcing Starliner to come back to Earth days early, on Dec. 22.

• In addition to the timer problem, a NASA and Boeing investigation team found another software issue corrected during the mission could have caused a major malfunction during the test flight had it not been caught.
• "The team found the two critical software defects were not detected ahead of flight despite multiple safeguards," NASA said in a statement. "Ground intervention prevented loss of vehicle in both cases."

The intrigue: NASA is also going to perform a safety assessment focused on Boeing's Starliner work and management.

• "The comprehensive safety review will include individual employee interviews with a sampling from a cross section of personnel, including senior managers, mid-level management and supervision, and engineers and technicians at multiple sites," NASA said.

What's to watch: NASA and Boeing are expected to complete their investigation by the end of the month.

• The agency will also decide whether Boeing will need to re-do an uncrewed test before flying astronauts for the first time.

Go deeper: Boeing's Starliner lands back on Earth after troubled mission