The space shuttle launch team completed a practice countdown Monday despite a fuel leak that raised the possibility of another postponement of a critical test firing of Discovery's engines. The leak halted fueling of the shuttle's hydrogen tank after it had been loaded with 254,000 gallons, 67 percent of capacity.
After assessing the situation, launch director Bob Sieck ordered the countdown to proceed to obtain data on other aspects of the count. The liquid-oxygen tank received a full load of 143,000 gallons and other procedures were rehearsed.
The countdown was stopped as planned at 11 seconds before a mock liftoff by a simulated problem, and the launch team began practicing steps it would take to recover from a postponement - making the shuttle safe, draining the propellants and turning the vehicle around for another countdown and launch attempt.
A second countdown is to end with the test firing of Discovery's three main engines. The firing had been scheduled for Thursday, but NASA said it might have to be delayed a day or so because of the leak.