The Important Aspect of Crew-9 Launch Not Being Talked About

Well, not being talked about much...  This was the first crewed mission from Space Launch Complex 40, (just called "slick 40" locally) using modifications to the pad that SpaceX has made over the last two years. 

Crew-9 was the 15th crewed launch by SpaceX, including the eight previous ISS crew rotation missions, Demo-2 test flight for NASA, three private astronaut missions to the ISS for Axiom Space and the Inspiration4 and Polaris Dawn private missions. All those previous missions, though, launched from Launch Complex 39A at the Kennedy Space Center rather than SLC-40, a pad dating back to the 1960s that hosted Falcon 9 launches since the vehicle’s debut in 2010.

SpaceX started work on a crew tower at SLC-40 two years ago at NASA’s request. The agency wanted a backup option in case something happened at LC-39A, which is used extensively by SpaceX for other Falcon 9 missions as well as the Falcon Heavy. SpaceX also has plans to launch its Starship vehicle from that facility.

NASA elected to use SLC-40 for Crew-9 because LC-39A is being prepared for the Falcon Heavy launch of NASA’s Europa Clipper mission as soon as Oct. 10, a process that takes at least three weeks to complete. NASA had planned to use LC-39A for the mission before the agency delayed its launch from August as part of deliberations on Starliner.

SpaceNews also reports that there have been some lessons learned about differences between LC-39A and SLC-40. A major lesson was a static firing done four days ago (9/24). Soot from the static test blew back onto the vehicle, requiring some work to clean surfaces on the Dragon spacecraft and repaint a radiator on the spacecraft to ensure it would operate properly in orbit.  The reason is that the flame trench on 39A is longer and points in a different direction: north instead of east like SLC-40. Since prevailing winds here are from the eastern quadrant, due east plus or minus 45 degrees, they might have to do that sort of work regularly.  

Liftoff from SLC-40 of the Crew-9 mission to the ISS Sept. 28. Credit: NASA

Remember when Elon Musk said an indicator of success would be if SpaceX makes launches boring?  Do they make news where you are? It was very cloudy here, and with the trajectory going to the northeast (which is the worst direction for us) we sat indoors and watched it on NASASpaceflight on YouTube.