Strange decision. Driven by desire to reduce assembly and test costs may be. From strength perspective, the failure looked like methane tank broke along weld line. The staggered pattern of sheets would at least make failure slower...mfb said:They will keep stacking rings, but the rings will be single steel sheets.
Seems the Starship is using stressed outer skin architecture if not integral bulkhead.mfb said:The steel mills don't produce endless sheets and you can't transport sections well if they become too long.
What broke was the connection of the bulkhead to the outer structure, that is not the welding of the outer structure.
I split this into a separate thread.
I agree with sequence of events, but not with conclusion. The tank have imploded under differential pressure of no more than 70 kPa (likely about 20 kPa). This is not the way a well designed tank intended to withstand the stress of hypersonic ascent should behave. For example, Space Shuttle Max-Q dynamic pressure during ascent was 33 kPa. Therefore, i.m.h.o., the implosion failure mode do indicate a too flimsy construction of Starship fuel tank.etudiant said:No expert, but it seemed to be a failure at the bottom of the tank, presumably the place where the valve fittings are mounted. The actual tank structure appeared then to implode, presumably because the pressurized LN2 burst out of the breach leaving a near vacuum behind.
If correct, this should be fixable fairly quickly.
That is what i call "flimsy construction". Baloon tank which do not tolerate even small damage. Initially SpaceX boasted construction to be much more stable and rigid than Atlas III at same fuel fraction, but after all Starship fuel tank seems to behave similar to Atlas III.mfb said:The dynamic pressure on ascent is along the direction of the rocket, not orthogonal to it. It's also nowhere near the tank section. The pressure on descent is orthogonal to the rocket axis but the tank will be pressurized to keep the interior pressure higher.
The failure was reportedly at the engine mounting, which was not adequately designed. The tank itself seemed just fine in both cases, just imploded after the failure at the fittings.mfb said:A comparison how quality improved over time:
SpaceX already has the key segments of the tank section (the parts where bulkheads need to be attached), so we can expect more tank pressurization tests soon.
The failure of the Starship Mk1 pressurisation test was caused by a leak in the cryogenic propellant system. This led to a rapid depressurisation of the tank and ultimately resulted in the failure of the test.
No, there were no injuries reported during the pressurisation test failure. The test was conducted remotely and all safety protocols were followed to ensure the safety of personnel.
The pressurisation test failure highlighted the need for further testing and improvements in the design of the Starship Mk1. It also serves as a learning opportunity for the engineers and scientists involved in the program.
The pressurisation test failure is expected to delay the timeline for the Starship's first flight. Further testing and modifications will need to be done before the vehicle is ready for its first launch.
The team at SpaceX is conducting a thorough investigation into the pressurisation test failure and implementing necessary changes to prevent similar failures in the future. This includes improvements to the design and testing processes for the Starship Mk1.