The 10th SpaceX Starship prototype, the SN10 was tested for a 10km high-altitude flight at the spaceflight company’s Boca Chica, Texas launch site. This time SpaceX was able to successfully land the Starship back to the landing pad contrary to the SN9 and SN8 landing failures.
Like the SN9 prototype, the Starship SN10 perfectly reached the intended altitude of 10 km, all three Raptor engines were shut down one-by-one to perform the belly-flop. The descent of the Starship was also flawless this time and re-ignition of the Raptor engines at 2 km height was also successful.
A Starship prototype has landed back on the landing pad for the first time and this should be considered a success for SpaceX not a failure.
By looking at the landing footage from the ground camera time and time again I was able to see some unusual flames around the engine exhausts, comparing it to the SN9 landing, it seems fairly unusual (see side-by-side photo below).
Although Starship Serial Number 10 (SN10) stood vertical on the landing pad for a few minutes then the explosion from the engine compartment made the spaceship prototype jump high into the air.
This explosion can be seen in the video of Boca Chica observer Trevor Mahlman’s video below, I took the following screenshot from his video showing the fire erupting from the tail-end. SpaceX removed the explosion part from the Starship SN10 high-altitude test flight official video (also below).
Update: As we suspected, the newer closeup footage of SN10 landing and further explosion shows the engine bay was actually on fire. Looks like a methane vent leaked and due to the high temperature and the presence of supporting factors, the fire further spread inside SN10, the explosion was enormous.
Some think that this happened due to the tiny short legs of the SN10 and the landing speed was still more than it should have been. Comparatively, SN9 restarted engines at 1.5 km for landing and SN10 did the vertical flip maneuver at 2 km. SpaceX might need to prepare for landing a bit sooner than even 2 km perhaps.
Elon Musk said “SN10 is in Valhalla now” — let’s watch its glorious demise from the closes view of the landing pad.
Musk further explained the reason for the SN10 crash in a later tweet, saying the landing engine was low on thrust due to probably partial helium ingestion from the header tank. The low thrust resulted in the legs crashing, he said. The Starship SN11 is going through multiple fixes to avoid this situation during the next launch and landing.
How tall is the Starship?
Starship spaceship without the Superheavy rocket booster has a height of ~52 meters — this is taller than a 13 story commercial or 17 storied residential building which is normally ~50 meters tall. This megastructure might not look that big on the screen but landing the Starship back on the ground is one of the most complex engineering challenges humanity has ever faced.
With the Superheavy rocket booster attached, the height of Starship will be 124 meters, even taller than NASA’s mighty Saturn V.
3D artist Nick Henning rendered a height comparison picture of different structures functioning at SpaceX Boca Chica launch site. Here’s the list with relevant heights;
- Starhopper 18 m
- Onion tent 21 m
- Low bay 30 m
- Mid bay 47 m
- Starship prototype 52 m
- High bay 81 m
- Superheavy booster 72 m
- Orbital launchpad/tower 156 m (estimated)
- Starship/booster stack 124 m
Starship SN10 test flight events:
- T- 2 mins 30 secs; finished up propellant loading.
- T+ 2 mins; preparing to transition from 3 to 2 Raptor engines (1st engine turned off).
- T+ 3 mins; 8 km altitude attained, shutting down 2nd Raptor engine and switching over to header tank for 1 remaining engine.
- T+ 3 mins 54 secs; 10 km altitude attained. Starship in hover state, all engines shut down.
- T+ 4 mins 20 secs; Starship flips to the horizontal position, starts the descent.
- T+ 5 mins 45 secs; preparing to start all three Raptor engines and begin the flip sequence to attain the verticle position.
- T+ 6 mins 20 secs; Starship SN10 makes a historic landing.
- End: RIP Starship SN10.