Satellite fleet operator SES is awaiting a detailed explanation from SpaceX as to why the second stage of its upgraded Falcon 9 booster failed to reignite during a flight on Sunday before placing its communications satellite on the next launch of the rocket.
Meanwhile, SpaceX has denied a report that the second stage might have exploded after delivering multiple satellites in low Earth orbit during a demonstration of the upgraded Falcon 9 version 1.1.
Re-ignition of the Falcon 9 upper stage is required for the SES-8 communications satellite to reach geosynchronous orbit. SpaceX, which has never launched a payload to this orbit, is examining what caused the re-ignition failure of the upgraded Merlin 1-D engine.
SES is waiting to ship the satellite to Cape Canveral pending the explanation.
In an interview, [SES spokesman Yves] Feltes said Luxembourg-based SES nonetheless still expects SES-8 to be the payload on the next Falcon 9 launch. The mission, scheduled to take place in the coming weeks, will be the Falcon 9’s first to geostationary transfer orbit, the dropoff point for most telecommunications craft….
The fact that SES will be awaiting details from SpaceX “does not mean that we reject the flight as a qualification flight,” Feltes said. “We still plan to be on the next Falcon flight, once SpaceX has solved the problem. But we need a technical explanation. We do need reignition of the stage for our satellite.”
The spacecraft is scheduled to launch from Cape Canaveral later this month, although that flight could slip into November as SpaceX examines the cause of the failure. In addition, the government shutdown has suspended all launch operations at U.S. government spaceports.
Meanwhile, SpaceX has denied a report that appeared on the Zarya.info website implying that the second stage might have exploded after deploying its satellites. The website reported an unusual number of objects — 20 in all — being tracked by a service called SpaceTrack.
“We have no reason to believe there was an explosion of any kind,” SpaceX spokeswoman Emily Shanklin wrote in response to my inquiry. “Based on previous launch experiences, we do know its common that the first measurements from Space-Track are not always accurate and sometimes mixed up…usually takes a few days for them to sort it all out and that’s with fewer objects to track.”
Shanklin later expanded upon that explanation in an email to journalists.
“Following separation of the satellites to their correct orbit, the Falcon 9 second stage underwent a controlled venting of propellants (fuel and pressure were released from the tank) and the stage was successfully safed. During this process, it is possible insulation came off the fuel dome on the second stage and is the source of what some observers incorrectly interpreted as a rupture in the second stage. This material would be in several pieces and be reflective in the Space Track radar. It is also possible the debris came from the student satellite separation mechanisms onboard.”