A misaligned seal may have caused a hydrogen gas leak that canceled space shuttle Discovery's launch attempt Nov. 5, officials said.
Technicians conducting repairs removed a metal plate and assembly that connect a gas vent line to the shuttle's external tank.
The vent line routes excess hydrogen to a flare stack to be burned off a safe distance from the vehicle, Florida Today reported.
A flight seal that remains on the tank after liftoff was found to be misaligned, the newspaper said.
During fueling in advance of last week's intended launch, a "significant" and potentially dangerous leak of gaseous hydrogen was detected where the vent line attaches to the tank.
Replacement of the seal, a quick-disconnect device and the vent line attachment plates was expected to be completed Friday.
Discovery's new seven-day launch window for what will be its final mission will begin Nov. 30, NASA said.