Following a short stay at the production site, Booster 9 has made its way back to the Orbital Launch Mount for additional testing before its test flight.
One major change SpaceX made to Booster 9 was the addition to the top of the booster. A vented interstage was attached to allow for Starship’s engines to ignite before separating from the booster, a method known as hot staging.
It is unknown if SpaceX changed out any Raptor engines on the booster after the previous test fire.
SpaceX was going to move the booster back to the OLM a bit earlier. However, Tropical Storm Harold formed and was heading toward Starbase. Thankfully the storm made a slight turn to the North, and no major impacts occurred at Starbase.
Once Booster 9 arrived at the launch site, it was lifted via the ‘chopsticks’ and onto the launch mount.
It didn’t take long for SpaceX to begin this test campaign as they partially filled the booster with liquid oxygen and performed a spin prime test of the engines. A spin prime test consists of flowing super chilled liquid oxygen through the Raptor engines’ turbopumps that simulate firing the engines just one step short of actually lighting them.
The next step will be another static fire test for Booster 9. The last attempt ended abruptly as 4 Raptor engines shut down early during a planned 5-second test, and the other 29 engines ran for 2.74 seconds.
As for a potential launch date, a new NOTMAR or Notice to Mariners has been issued for September 8th, and Elon Musk recently stated that the next Starship launch will be “soon.”
While hopeful, it is unlikely to launch by September 8th. However, there is a high chance it won’t be much longer of a wait once the static fire is complete and the company gets the all-clear from the FAA.
A clear sign that the 2nd integrated test flight is imminent will be the issuance of the NOTAM (Notice to Air Missions) and, of course, Starship being stacked atop Booster 9 and the flight termination system installed.