A rocket this size can always be halted with some piece of hardware refusing to move as required. It may look like a dramatic event because the Starship V3 launch attempt was scrubbed in the last minute, but there is something more important about SpaceX’s inability to proceed further. The fact is that SpaceX engineers decided that this rocket, new launch site, and elaborate ground systems are not yet good enough to pass the threshold of being launched, and it tells a lot about the peculiarities of building heavy-lift launch vehicles. The thing is that launches like that are sometimes halted not because something goes wrong, but to show that the process can still fail.
In case with Starship V3, there are two possible explanations related to SpaceX’s decision. Namely, they mentioned the problem with hydraulic pins holding the arm of the tower and a water diverter under the mount, which are exactly the kind of issues that prevent even fully fueled and prepared for the launch rocket from getting off the surface.
As launch professionals claim, such an outcome should be considered usual for rocket launches because of the complicated nature of such a process. Speaking of his experience with NASA’s launches, UCF planetary scientist Phil Metzger said that there’s so many things that can go wrong and it takes years of work to get everything to the point that you’re ready to try to orchestrate it. Moreover, he explained that chances of stumbling upon something are higher for new kinds of rockets during early tests.
These comments explain why it is particularly relevant in the case of Starship V3 launch. It does not include only a slightly bigger launch vehicle, but also a set of changes related to the redesign of the launch pad and even a vehicle, with the latter including, among other improvements, a booster with three bigger grid fins and a hot-stage ring kept on it rather than being dropped after launch.
Moreover, there are also major changes in the propulsion system. First of all, Starship uses the engines featuring the full-flow staged combustion cycle, which makes them superior for performance and future reusability. Besides, SpaceX claims that V3 generation is lighter than previous ones and includes better integration. Moreover, Starship V3 includes other upgrades aimed at improving the plumbing and reducing the dry mass. This is why it is not just a side story.
When it comes to heavy rockets, all of these details make the pad itself a part of the rocket and, accordingly, the whole launch system. Namely, it includes tower arms, the quick disconnect hardware, diverter system, pumps and valves, and countdown software. As Mr. Metzger said, all the launch operations begin with extensive contingency procedures, and then engineers decide whether troubleshooting is possible within a launch window. The phrase he used sounded very clear and concise: “[Scrubbing a launch is] always a really tough, real-time decision.” Thus, the failure in this case means that the launch system worked perfectly as expected by rejecting the launch.
At least for now, the halted countdown only confirmed one thing. Namely, it is known that SpaceX plans Starship to play the central role in the Artemis lunar program as its landing module, and they are also promoting this vessel for bigger commercial missions and satellites deployments. Moreover, the planned test profile included dummy payload deployment for Starlink, on-orbit imaging of the heat shield, re-entry maneuvers, and the subsequent splashdown to confirm the capability of the Starship to perform as a transport platform.