Tuesday, May 21, 2024

Starship Flight Test 4 Looks to be Within 2 Weeks

Two weeks according to Elon Musk. As usual, think of it as Elon Standard Time, but here's the full story.

"Starship Flight 4 in about 2 weeks," Musk posted on X, his social media platform, following a Starship countdown rehearsal Monday at the Starship launch site in South Texas. "Primary goal is getting through max reentry heating."

The article there on Ars Technica begins with the absolutely valid observation that the first three test flights have demonstrated that Starship can lift off the pad, stage properly, and can make it to orbit.  Now, it's time to prove that Starship can reenter and get back home. That will be the emphasis of Integrated Flight Test 4, or IFT-4. 

In case you missed it, on Monday, SpaceX at Starbase carried out a wet dress rehearsal of the Booster 11, Starship 29 stack, filling the nearly 400 foot tall rocket with 10 million pounds of super-cold methane and liquid oxygen. The WDR didn't culminate in a static firing, but covered everything up to the final steps before firing.

SpaceX then drained the cryogenic propellants from the rocket, and ground teams removed the Starship upper stage from the booster Tuesday for more work on the ship's heat shield. A few days before launch, SpaceX will install the rocket's self-destruct mechanism, which would be used to destroy the vehicle if it flies off course and threatens populated areas.

As always, the FAA must grant SpaceX a license to launch before they may. It's reported that they are still going over SpaceX's internal review of the IFT-3 mission back in March. The FAA considered that flight a mishap because the Starship lost control and disintegrated during reentry before it could make a targeted intact splashdown in the Indian Ocean. For SpaceX, the March flight was a resounding success. It was the first time a Starship test flight reached near orbital velocity, with full-duration burns by all 39 Raptor engines on the rocket's first and second stages.  

March's IFT-3 tested a few different things, such as performing a propellant transfer inside the Starship and opening the "Pez Dispenser" door that will be how Starlink satellites are deployed. (All indications continue to say that the propellant transfer worked properly). IFT-4 will focus on controlling the reentry of both the booster and Starship. Both the booster and ship of IFT-3 broke up during their descent.

SpaceX officials would like to see the Super Heavy booster for the next test flight, named Booster 11, make a controlled pinpoint splashdown in the Gulf of Mexico just offshore from Starbase. Halfway around the world, the Starship upper stage, known as Ship 29, will try to survive the blistering reentry back into Earth's atmosphere.

Starship is dressed in about 18,000 hexagonal heat-absorbing ceramic tiles to protect its stainless-steel structure during reentry, when temperatures peak at about 2,600° Fahrenheit (1,430° Celsius). In the final moments of the March test flight, onboard cameras captured spectacular video of the pinkish-orange glow of plasma flowing over the vehicle high over the Indian Ocean. This video was downlinked back to Earth through SpaceX's Starlink broadband network.

This rear-facing camera, mounted inside one of the forward flaps on Starship, shows plasma building up around the underside and rear flaps during reentry over the Indian Ocean.  Image credit: SpaceX 

Musk wants to see Starship survive the highest temperatures of reentry with all systems functioning. Remember, the ultimate goal here is a Return to Launch Site landing of the booster and rapid reuse. Musk has teased that SpaceX could try landing a Super Heavy booster back at the launch pad in Texas as soon as the next flight test. Since we're looking at maybe one week less than three months between the last IFT and this coming one, assume the same three months and the booster returning to Boca Chica to get caught by the chopsticks would be in September.


  1. SiG, the FAA decided that since both vehicles didn't have problems over populated areas, they would forgo SpaceX waiting for the analysis report. They will go ahead and make the launch license effective after Memorial Day, letting everybody have some time off... Federal Agency, don'cha know!

    And, the WDR showed how SpaceX's efforts to get a faster fill of both Booster and Starship appeared to be effective - it only took 45 minutes to fill both!

    Now that they have more aggressive roil thrusters, survival should be in the 90% range. Lets hope! The rear-facing camera mounted in the flamp will give us some spectacular video, let's hope it survives the re-entry.

  2. A lot of what is called Elon time in regards to SpaceX is now bureaucrat time. SpaceX needs to hire Boeing fixers.

  3. Hope their re-entry shielding holds up well from low earth orbital speed, because its going to need to have a designed in buffer range for when they re-enter at higher velocities coming in from the Moon and Mars.

    Imagine that will be one heck of a celestial event, that starship is about the largest object to re-enter Earth atmosphere, look like the grandest meteor in history, across the entire horizon and then some for how much velocity they must shed.
    Which brings up an interesting thing here with the heat shield problems Lockheed and NASA are having, I mean Appollo on the moon returns made it back ok, why they are not employing earlier NASA tech is a real head scratcher. Snd they did it with slide rules and little if any digital mapping back then. If I remember back then right, watched a TV special about the heat shield materials used, it was not much more than pretty thick phenolic, its a great material, been around in one form or another since WWII if not mistaken. Know from using it for knife handles and skid pads its truly rugged material.

    1. Wanted to add its rather dense so its pretty heavy stuff, and thats always a trade off, what with mass being so critical and everything.