A NASA official commended the launch team for making a "tough call", after the first crewed flight of Boeing's Starliner spaceship was dramatically called off around two hours before launch after a new safety issue was identified. Astronauts Butch Wilmore and Suni Williams were strapped in their seats preparing for liftoff when the call for a "scrub" came, in order to give engineers time to investigate unusual readings from an oxygen relief valve on the second stage of the rocket. "I really commend the team for making that tough call, it was really impressive to watch them work through the problem, now we'll take the next day or so to look at the data and to recommend the next course of action," Steve Stich, manager for NASA's Commercial Crew Program said at a press conference. SOUNDBITE