A potentially dangerous hydrogen fuel leak on the space shuttle Discovery thwarted NASA efforts to launch the spacecraft today, delaying the shuttle’s final liftoff to no earlier than Monday, Nov. 8. Discovery was slated to launch at 3:04 p.m. EDT (1904 GMT) today (Nov. 5) but a leak of flammable liquid hydrogen discovered during fueling forced NASA to stand down.
Midway through the fueling process Friday, hydrogen gas began leaking from the attachment point for a vent line on the external fuel tank. It’s the same type of problem that forced delays for two shuttle missions last year, and had not reoccurred since then. Managers halted the countdown two hours after fueling began. The six astronauts had yet to board the shuttle. Discovery’s final mission already had been running four days late because of technical and weather problems.
NASA has until Sunday to send the shuttle to the International Space Station. Otherwise, the flight will be off until December because of unacceptable solar angles. Nasa later said there would be no launch attempt on Friday. The next attempt will be made no earlier than Sunday, but if lift-off does not take place then the mission is likely to be postponed until next month.
Technicians discovered the leak while filling Discovery’s distinct, orange external tank with liquid oxygen and liquid hydrogen. This procedure, known as tanking, fills the external tank with the 520,000 gallons of cryogenic propellant that will be used to fuel the shuttle during liftoff and ascent into space. Discovery will fly an 11-day supply mission to the International Space Station to deliver a humanoid robot helper for the station crew and a new storage room for the orbiting lab. The orbiter has already faced down a series of setbacks, including a pair of gas leaks, an electrical glitch and, most recently, uncooperative weather. The mission will be Discovery’s grand finale in space before being retired along with the rest of NASA’s shuttle fleet in 2011.