As expected, SpaceX and NASA announced Wednesday that they have rescheduled Monday’s scrubbed launch of a Falcon 9 v1.1 carrying a Dragon cargo spacecraft to Friday, with the launch scheduled for 3:25 pm EDT (1925 GMT). A backup launch date is Saturday at 3:02 pm EDT (1902 GMT). As of Wednesday, forecasts still called for only a 40% chance of acceptable weather on Friday, increasing to 70% on Saturday.
SpaceX also shared some additional details about the scrub, which was announced more than an hour before the scheduled liftoff time Monday afternoon. “During Monday’s launch attempt, preflight checks detected that a helium valve in the stage separation pneumatic system was not holding the right pressure. This meant that the stage separation pistons would be reliant on a backup check valve,” the company said in a statement. “No issue was detected with the backup valve and a flight would likely have been successful, but SpaceX policy is not to launch with any known anomalies.” Space X added they are replacing the faulty valve and performing other checks on the vehicle.
If the launch slips past Saturday, though, it’s possible this particular mission could face an even longer delay. Speaking at a meeting of the NASA Advisory Council (NAC) in Washington on Wednesday, Bill Gersetenmaier, NASA associate administrator for human exploration and operations, indicated that further delays might see NASA instead press ahead with a May 6 launch of an Orbital Sciences Corporation Cygnus cargo spacecraft on an Antares rocket from Virginia.
“We have a flight we’re trying to get off this Friday,” Gerstenmaier said of the upcoming Dragon launch. “If that doesn’t occur, we’re going to use the Cygnus vehicle on May 6. So I’m kind of double booking two launches at once for a little while until we see what actually occurs, because we’re getting low enough on supplies on board station that we’ve got to get something to station in the next couple of months.”
He added that if the Dragon launch does go off as scheduled this Friday or Saturday, NASA would delay the Cygnus launch until June 9.