SpaceX

Responding to a Twitter user, Musk says SpaceX Starship with improved Raptor 3 engines should lift 300 tons in expendable mode, or 180 tons in reusable mode.  This compares with two years ago, when Two years ago Musk estimated a Starship would lift 250 tons to orbit in expandable mode and 150 tons in reusable mode. For comparison, the International Space Station weighs 450 tons and took around 50 Space Shuttle launches to complete. An earlier, SpaceX concept, called the Interplanetary Transport System, was planned to carry 550 tons expendable, 300 tons reusable.

Starship payload is 250 to 300 tons to orbit in expendable mode. Improved thrust & Isp from Raptor will enable ~6000 ton liftoff mass.

Starship payload is 250 to 300 tons to orbit in expendable mode.

Improved thrust & Isp from Raptor will enable ~6000 ton liftoff mass.

— Elon Musk (@elonmusk) May 24, 2023

In an audio chat with SpaceX fans, Musk says Starship’s first test flight was successful, even though it exploded before reaching space, and says a new rocket can be ready for liftoff within six to eight weeks, along with repairs to the damaged launchpad.

The outcome was roughly in what I expected, and maybe slightly exceeding my expectations, but roughly what I expected, which is that we would get clear of the pad. [The launch was] obviously not a complete success, but still nonetheless successful.

Musk says he hadn’t expected a “rock tornado” to be generated under the booster at liftoff and said SpaceX “chose not to start” three of the 33 Raptor engines on the booster, because they were not “healthy enough to bring them to full thrust.” Musk also said the reason Starship slid off the launchpad while ascending was “because of the engine failures.” SpaceX “lost communications” with another Raptor about 27 seconds into the flight due to “some kind of energy event” that knocked the heat shields out of several other engines.

At about 85 seconds, “things really hit the fan” and SpaceX lost its ability to steer the rocket. Finally, Starship’s Automated Flight-Termination System was working too slowly, so it took about “40 seconds-ish” to self-destruct. Still, Musk downplayed the effects of the explosion as a whole, saying the (Boca Chica) “pad damage is actually quite small” and should “be repaired quickly.”

Despite the fact that debris from the explosion fell into the Gulf of Mexico and rained dust onto residents of Port Isabel (as well as their cars and homes), that the U.S. Fish and Wildlife Service called the explosion responsible for a 3.5-acre fire, the spread of debris over 365 acres of land, and throwing of “pulverized concrete” up to 6½ miles, Musk says:

To the best of our knowledge there has not been any meaningful damage to the environment that we’re aware of.

Musk believes, too, that the Starship program does not need $750 million in additional funding it had been set to raise, and will spend about $2 billion on the Starship program to attempt five launches. Musk says he expects success by the end of the year;

I will be surprised if we exit this year without getting to orbit.