NASA’s new boss blasted Boeing and the space agency Thursday for Starliner’s botched flight that left two astronauts stuck for months at the International Space Station.

Administrator Jared Isaacman said poor leadership and decision-making at Boeing led to Starliner’s troubles. He also blamed NASA managers for failing to intervene and get Butch Wilmore and Suni Williams back more quickly.

The two test pilots, now retired from NASA, spent more than nine months at the station before catching a lift back with SpaceX last March.

Isaacman said Starliner’s problems must be better understood and fixed before any more astronauts strap in.

Isaacman upgraded the seriousness of Starliner’s troubled astronaut debut, declaring it a “Type A mishap,” something that could endanger a crew. Both the Challenger and Columbia space shuttle disasters also involved cultural and leadership missteps. It is a mistake that Starliner was not designated a serious mishap right from the start, Isaacman said, citing internal pressure to keep Boeing on board and flights on track.

NASA boss blasts Boeing and space agency managers for Starliner's botched astronaut flight