Spacex newest Starship prototype (SN8) lit its engines in what was supposed to be a groundbreaking test fire, only to spit out what appeared to be sparks…suggesting that something had gone terribly wrong. While failures are to be expected in this revolutionary rocket project, this latest hiccup comes after a string of mishaps that stretch back over a year. So what went wrong this time and why is it a big deal?
The Starship Rocket
The Starship rocket, when completed, will be the largest rocket ever built, even dwarfing the mighty Saturn V. Unlike the Saturn V, however, Starship aims to be fully reusable, with the first stage landing back on Earth much like Spacex’s revolutionary Falcon 9 rocket. The upper stage, which is what was tested here, will have flaps and a heat-shield that allow it to do a never-before performed ‘flip’ maneuver that will reorient the craft from reentering the atmosphere on its side, to perpendicular with the ground so that it may fire its engines for landing.
SN8’s goal is to prove out a this complex maneuver. While few expect that SN8 will be successful on the first try, it was immensely disappointing when the rocket malfunctioned during a ground static fire. Perhaps though, it should have been expected that there would be problems.
A Difficult Journey
The first prototype of the Starship rocket, known Mark 1, ruptured during pressure testing due to poor weld quality. This prototype was supposed to be performing the same tests that SN8 is today….over a year ago. The reason for the delay is that the failure of the Mark 1 brought with it a string of issues that the company has found it difficult to resolve.
The next prototype, called SN1 or “Serial Number 1” also ruptured in pressure testing, but this time due to a poorly redesigned “thrust puck.” SN3 also ruptured, but due to ground equipment failure, and SN4 didn’t fair much better, successfully passing pressure tests, but exploding during ground testing before it could fly.
SN5 did successfully fly to a 150 meter altitude and achieved its own modest testing goals, but damaged itself on landing. SN6 repeated this maneuver successfully, but was not designed to perform the “flip” maneuver that it is being tested on SN8.
You’ll notice that some SN numbers are missing here and there is a reason for that. SN2, SN7, and SN7.1 were merely test tanks designed to evaluate new manufacturing methods, and were not intended to fly or even light engines. For this reason, I am not sure we can consider them to be “prototypes” at all.
What Went Wrong This Time
According to Elon Musk, SN8’s engines kicked up shards of ceramic coating from the concrete of the launchpad, these shards flew back into the rocket, severing the avionics control lines. The craft itself likely can be repaired, but the incident calls into question the design of the rocket entirely. Elon Musk has admitted as much, remarking that they “might” make some “notable” changes to the design.
If the craft cannot safety take off from a pre-prepared launchpad on Earth without causing damage to itself, it will certainly not be able to take off (or land for that matter) on the rocky, dusty, and unprepared surface that one would find on Mars or the Moon. That’s a problem….a big problem.
Spacex might need to rethink the placement of the engines entirely. While I have no doubt that Spacex engineers are up to the task of solving this complex problem, the question is how much of a delay this will ultimately add to the program and how substantial the design changes are going to need to be.