SpaceX continues to press on with pre-flight testing for Flight 9, while internally looking to resolve issues with the Ship that has resulted in the loss of the first two Block 2 vehicles. Ship 35 and Booster 16 – the potential pairing for Flight 9 – have been cryotested at the Masseys test site.
Booster 15
As was the outcome of Flight 7, the only successful part of Flight 8 was the Booster. Booster 15’s ascent was perfect, and SpaceX has now completed four flights without an engine out on ascent.
During boost back burn, two out of 13 engines failed to ignite, which resulted in a longer burn. Then, during landing, one of the same engines that was unable to reignite for the boost back burn also failed to ignite. These failures were on the inner ring of 10 engines and not on the center three. Despite the failures, Booster 15 showcased some of Super Heavy’s engine-out capabilities.
Booster 15 Landing (Credit: BocaChicaGal for NSF)
During the landing burn, SpaceX showed off what looked like a new landing profile where the booster came in through the arms more vertically than horizontally. It also showed that the arms can adjust for an off-center booster, as Booster 15 landed off to the left of center.
After the catch was completed, the chopstick arms rotated the booster to the left, potentially to cancel out the swaying the booster observed with the past two catches.
Overall, Booster 15 completed its objectives and was caught for possible reuse; however, SpaceX will want to evaluate the engine outs.
Booster 15 Return to Production Site After Catch (Credit: Rough Riders Show for NSF)
Ship 34
Ship 34 did not complete its objectives and was lost following what looks like a Raptor Vacuum engine explosion at around T+8 minutes and 7 seconds. This resulted in losing all three Raptor center engines, leading to off-axis thrust. This led to an uncontrolled tumble, after which the Ship was destroyed during reentry or had an additional explosion.
This, in turn, led to a large debris field over the Bahamas and the Turks and Caicos Islands, requiring ground stops of aircraft attempting to fly out of southern Florida. Due to this anomaly, the Federal Aviation Administration is requiring SpaceX to perform a mishap investigation into the failure on Flight 8, while the mishap for Flight 7 is still open.
Expected. The @FAANews is requiring a mishap investigation into Flight 8 of Starship. pic.twitter.com/TG6zKS2pwC
— Adrian Beil (@BCCarCounters) March 7, 2025
The Raptor Vacuum failure may have been caused by the regenerative cooling manifold on the nozzle extension burning through, potentially caused by uneven Liquid Methane flow through the propellant lines. A large uncontrolled propellant leak into the engine bay was seen at around T+7 minutes and 50 seconds. This resulted in a fire that then led to the demise of Ship 34.
SpaceX mentioned that the leak on Ship 33 was caused by a harmonic resonance, meaning vibrations in the ship were resonating and causing damage. However, the fact that Ship 34 was lost due to an engine fire again suggests that the issue may not be solved entirely.
This issue may stem from changes that SpaceX made to the Ship design for Block 2. In those changes, the methane transfer tubes for the Raptor Vacuum engines went from being piped off the main center transfer tube to being three separate tubes, one for each Raptor Vacuum. These lines might be too long and thin, and once the Liquid Oxygen (LOX) tank gets empty near the end of the Ship’s ascent burn, they vibrate at just the right frequency.
Starship Flight 8: That's not nominal. Ship 34 in a spin. pic.twitter.com/s2R0JfSnhk
— NSF – NASASpaceflight.com (@NASASpaceflight) March 6, 2025
If those lines were to resonate with the engine vibrations and other propellant lines, severe damage could occur, leading to a break or a much higher leak rate than any onboard purge system could dissipate. This would then lead to a possible engine fire and the loss of the ship, as well as cause disruptions in the flow to the engines, possibly leading to the issue on the Raptor Vacuum engine.
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This kind of problem is very hard to test on the ground because SpaceX uses LOX as ballast to hold the ship down during the static fire. The liquid would dampen vibrations inside the LOX tank, preventing accurate data.
Without official word from SpaceX, it is unknown if this is the real problem or, if it is, when it will be fixed. SpaceX CEO Elon Musk stated on X that this is a minor setback, and the next ship should be ready within four to six weeks.
Whatever the issue is, it could be fixed in that amount of time, but SpaceX has just lost two ships in a row at around the same time during ascent. If SpaceX and Elon Musk want to prevent timelines for propellant transfer, ship catch, and many other milestones in the Starship program from slipping further, SpaceX can’t really afford to lose a third in a row.
Ship 33 Transfer Tubes (Credit: BocaChicaGal for NSF)
Future Ships
Following the failure of Ship 34, SpaceX did not stop Ship testing and production. Ship 35 has completed three cryogenic proof tests and should be returning to the Production site this week. Ship 36 had its transfer tubes installed the night of the launch, after crews returned to work. And has since had its engine section installed as well, thus completing the stacking work for Ship 36.
It is currently unknown what the full solution to the current problem is with ship. If it’s not very invasive, then Ship 35 and Ship 36 would be able to have retrofits completed so that either ship doesn’t suffer the same fate. However, if the fix is far more complicated, then both Ships could end up scrapped while SpaceX does redesigns for Ship 37.
Overall Starbase is going to be very interesting to watch over the coming weeks to see what fate awaits Ship 35 and Ship.
Featured Image: Flight 8 Liftoff (Credit: Max Evans for NSF)