In a new NASA briefing, SpaceX Vice President of Building and Flight Reliability Hans Koenigsman was able to explain in more detail why another disappointment occurred to the Falcon 9 launch and how it ended up delaying the launch of the company’s first operational astronaut.

Now scheduled to take off no later than (NET) 7:49 PM EST (00:49 UTC) on Saturday November 14, SpaceX’s Crew Dragon Crew-1 mission was originally expected to launch in late September, 23 October 31st. However, on October 2, the new Falcon 9 booster – the brother of Crew-1’s new booster – automatically aborted the attempt to launch the GPS III SV04 satellite just two seconds before takeoff. Soon the rare last-second miscarriage was blamed on an “unexpected high pressure in the turbine gas generator” by CEO Elon Musk.

Probably synthesized in conjunction with faulty GPS III SV04 Falcon 9 Booster B1062 at SpaceX’s Hawthorne, California, Crew-1 Falcon 9 Booster B1061 plant was examined almost instantly for any commonalities once the cause of miscarriage was better understood.

Just a week before the last briefing, NASA’s Human Spaceflight Program Director and former Commercial Crew Program director Cathy Loders revealed in a statement on Twitter that SpaceX was still analyzing the cause of the miscarriage but had already determined that at least one of the enhanced Crew-1 engines was They will need a replacement, as well as one engine on the Falcon 9 booster B1063.

Now, during a crew 1 briefing on October 28 for NASA, SpaceX’s Koenigsman revealed that the company had finally decided not to replace one but two of the nine B1061 Merlin 1D engines. Thanks to the design of the nine-engine booster of the same name from the Falcon 9 and the prolific SpaceX rocket manufacturer, this process was completed at an extraordinary speed, which simply required re-orientation of already qualified Merlin 1D engines from a fairly large group. Based on Koenigsmann’s formulation, SpaceX has already installed both alternative engines on the Crew-1 Booster.

However, what caused the SV04’s GPS III launch and how did that affect the Crew-1?

Rocket Engine Vs “Nail Polish”

According to Konigsman, in the context of the fast and complex mechanical and electrical ballet preceding the first stage of the Falcon 9 ignition, the missile autonomous flight computer noted that two of the nine Merlin 1D engines for the GPS III SV04 booster appeared to be operating ahead of schedule, so to speak. Immediately stop the computer ignition to avoid what would have been a “difficult” (ie stressful or harmful) start. SpaceX quickly began checking the missile within 24 hours, but was unable to detect any physical or electrical fault with Falcon 9’s Merlin 1D engines and engine division.

Out of extreme caution, SpaceX removed both the offending engines and shipped them to its development and testing facilities in McGregor, Texas where – somewhat miraculously – the same early startup behavior was replicated on the test stand. After a great deal of increased granular checks, SpaceX finally narrowed down the potential cause down to a small plumbing line feeding one of the engine’s gas generator drain valves. In a seemingly random subset of the relatively new Merlin 1D engines, SpaceX eventually discovered that the supplier’s relief valve line was sometimes clogged by a Koenigsmann protective coating that looked like “red nail polish”.

Used to selectively exclude portions of the engine tubes during the surface finishing process known as anodizing, the coating has either been removed unsuccessfully on a random set of engine parts or has been mistakenly directed into a clog due to excessive cleaning. Ultimately, for whatever reason, the slight clogging was enough to make affected Merlin 1D engines constantly try to ignite a fraction of a second early.

Crucially, when SpaceX discovered the possible cause and cleaned up the blocked plumbing, all previously affected Merlin 1D engine performed perfect, but all of this directly confirms the cause and remediation for the foiling of the Falcon 9 on October 2.

Astronauts enter quarantine

In anticipation of finding a seemingly simple solution to the gas generator problem, Steve Stitch, commercial staff program manager at NASA, revealed that SpaceX’s Crew-1 mission astronauts – Shannon Walker, Victor Glover, Mike Hopkins, and Japanese astronaut Soishi Noguchi – have begun Routine quarantine measures before launch in anticipation of the November 14 launch.

Stich also presented a more specific Crew-1 schedule, starting with the Falcon 9 static fire test and the Crew Dragon on November 9 and a full rehearsal on November 10 before the first launch attempt on November 14. Notably, thanks to the coincidental orbital dynamics, a successful launch on November 14 should enable the Crew Dragon to raise its orbit and meet the International Space Station eight and a half hours after takeoff – three times faster than the most common 27.5-hour transit.

Stay tuned for updates as the launch date approaches.