An Ars-exclusive interview shows that 4 thruster failures resulted in astronauts Butch and Sunni losing control of Starliner as it got close to docking.<p>Not only did the astronauts have to switch to manual control, but the loss of control eliminated the possibility of aborting and safely returning to Earth.<p>Quick thinking from Mission Control saved their lives - control was regained shortly before a fifth thruster was lost.<p>This paints a much more harrowing picture than NASA or Boeing originally provided to the public.