$ VXFFHVVIXO IDLOXUH

O NThursday last week, the most powerful rocket ever built was launched from Boca Chica State Park in South Texas. SpaceX’s Starship, designed ultimately to take up to 100 people to Mars, has almost twice the launch power of NASA’s Saturn V rockets, which took the Apollo astronauts to the Moon. At nearly 120 metres in height, it is the biggest and heaviest spacecraft yet created.

Before Starship’s launch, Elon Musk set a low bar for the mission: estimating a 50 per cent chance of success, he said that if the rocket gets ‘far enough away from the launchpad before something goes wrong, then I think I would consider that to be a success. Just don’t blow up the launchpad’.

The intention was to do a single orbit, with the second stage landing in the Pacific near Hawaii. The first stage, the Super Heavy Booster, was planned to make a controlled landing in the Gulf of Mexico after six minutes. The entire rocket is designed to

be reusable.

The launch was delayed for three days due to a frozen valve that couldn’t be fixed in time, so SpaceX held a ‘wet dress rehearsal’ for the mission, stopping 40 seconds before the rockets ignited.

Then on April 20, Starship’s 33 Raptor engines fired and the huge rocket lifted from the launchpad. At first everything seemed to be going well, but four minutes into the flight, as the second stage was supposed to separate, the rocket started spinning uncontrollably and ended up heading straight back down to Earth with all its engines still firing.

LAUNCH

“Obviously, this is not a nominal situation,” said the launch commentator.

A few seconds later, the rocket was blown up by the rocket’s flight termination system. A tweet from SpaceX described this as a ‘rapid unscheduled disassembly’ or RUD, a common space industry term, which was nonetheless the subject of many amused comments on social media.

“As we promised, excitement is guaranteed. Starship gave us a rather spectacular end to what was truly an incredible test,” said the launch commentator.

Elon Musk had good reason to fear damage to the launch pad. Amazingly, for such a powerful rocket, the launchpad was built without flame diverters

or sound suppression systems, which prevent damage to the pad on launch. This is apparently in anticipation of Starship being launched from Mars, where it would be difficult to build such protective systems.

There was indeed severe damage to the pad and the surrounding infrastructure, with a cloud of concrete dust being blown 10km to the northwest, including into neigbouring communities. One commentator speculated that damage might have been done to the rocket by blast fragments. In 2020, Elon Musk tweeted “Aspiring to have no flame diverter in Boca, but this could turn out to be a mistake.” For the biggest rocket ever launched, this would seem a no-brainer and the Starship launch started a one-hectare wildfire.

According to environmentalists of the Sierra Club, the blast also caused road damage that blocked wildlife biologists from investigating the site until two days after the launch. SpaceX may have to rethink those flame diverters. This reminds me of the Apple III computers, which were built without cooling fans, because Steve Jobs didn’t like the noise. The computer’s components warped and even melted in the heat. Apple issued instructions to users to lift their computer by a centimetre and then drop it on the table, to make the circuits settle back in place. Sometimes even the best engineers try to be too clever.