NASA Optimistic About SpaceX Engine Fixes, but Wants GPS III Launch Before Crew-1
NASA and SpaceX held a teleconference today to explain the Falcon 9 engine problem that led to a delay for the Crew-1 flight to the International Space Station. SpaceX has determined and fixed the cause of the anomaly that scrubbed the launch of a DOD GPS III satellite on a Falcon 9 earlier this month, but some changes were required and NASA wants to see the GPS III launch take place before finally committing to launching Crew-1 on November 14.
The launch of the fourth satellite in DOD’s GPS III series of positioning, navigation, and timing satellites, GPS III-4, was scrubbed just two seconds before liftoff on October 2. At the time, launch of the first operational Crew Dragon mission to ISS for NASA, Crew-1, carrying four astronauts was scheduled for October 31.
SpaceX’s Falcon 9 rocket is used both for launching people into space and satellites. The Falcon 9 engines are named Merlin.
NASA decided to delay the Crew-1 launch saying SpaceX was looking into “off-nominal behavior of Falcon 9 first stage engine gas generators.”
Today, SpaceX Vice President for Build and Reliability Hans Koenigsmann explained that residue from a nail-polish like substance — a masking lacquer — used to clean engine components had blocked a 1/16 inch relief valve, triggering an automatic abort. He called it a “good” abort because software did what it should have done, preventing possible damage to the engines.
The anomaly affected two of the nine Merlin engines on the Falcon 9 that day. Inspection of other Merlin engines found similar problems with two that were slated for the Crew- 1 rocket and one for launch of an earth science satellite, Sentinel-6 Michael Freilich, from Vandenberg Air Force Base, CA on November 10.
SpaceX is replacing all five engines.
Kathy Lueders, head of NASA’s Human Exploration and Operations Mission Directorate (HEOMD), said the Sentinel-6 Michael Freilich launch and that of Crew-1 were unrelated and each would be launched when ready.
Steve Stich, program manager for NASA’s commercial crew program, which Lueders headed until June when she was promoted to her current position, later said, however, that NASA wants to see the GPS III-4 launch take off before committing to the Crew-1 launch date.
In terms of what we would like to see, one of the engines that we’re installing on the first stage has a slight change that we would like to see go on the GPS III mission first. So we’re talking to our team and SpaceX right now. We would like to see that one mission go fly before we fly crew. — Steve Stich
If the Crew-1 launch takes place on November 14, it will be one of the best launch windows orbital dynamics allows. Only 8.5 hours will be needed for the crew to reach ISS. Launch will take place at 7:49 pm ET and the crew will dock at 4:04 am ET November 15.
That is a sweet spot, to be sure. Most of the time the rendezvous duration is closer to 28 hours, similar to the Demo-2 mission launched on May 30 as a test flight to pave the way for operational missions.
NASA and SpaceX are moving forward based on the November 14 launch date. The four-person crew is already in a soft quarantine at home with their families. They will transition into a more stringent quarantine on October 31 and travel to Kennedy Space Center on November 6. A dress rehearsal will take place on November 11 in preparation for the November 14 launch.
If the November 14 launch date slips to November 15, it will take place at 7:27 pm ET. Stich said that date, just one day later, takes them back to the “normal” rendezvous duration of about 28 hours.