Honestly, if you watched the live stream of SpaceX's Starship Flight 4 back in June 2024, you probably thought you were witnessing a slow-motion disaster. For several minutes, a high-definition camera showed a forward flap literally melting. Red-hot plasma was eating through the metal like a blowtorch through butter. Debris was flying off into the void.
It looked like the end. But then, the ship didn't explode.
That single mission—officially known as Integrated Test Flight 4 (ITF-4)—is arguably the most important moment in the program's history so far. It wasn't about "getting to space." They'd done that already. It was about proving that this 165-foot-tall stainless steel beast could actually survive the return trip without turning into a multi-million dollar firework.
The Flap That Wouldn't Quit
The most visceral part of Starship Flight 4 was the re-entry. Most spacecraft go through a "blackout" period where the heat of re-entry blocks radio signals. Not Starship. Thanks to the Starlink terminals on board, we got a front-row seat to the ship screaming back into the atmosphere at Mach 25.
About 45 minutes into the flight, the plasma started to build. It was beautiful at first—a soft purple glow. Then it turned into a fierce, angry orange. That’s when things got dicey.
The camera showed the hinge of the forward flap taking a direct hit. The seal had failed. You could see the structural skeleton of the flap glowing white-hot. Liquid metal was spraying against the camera lens. Even the SpaceX commentators sounded a bit stunned that the telemetry was still coming through.
Despite a hole being burned straight through the control surface, the ship's software kept fighting. It compensated for the lost surface area and kept the vehicle stable. This wasn't just luck; it was a massive win for the "fail fast" engineering philosophy. It proved the airframe was way more resilient than anyone—possibly even Elon Musk—expected.
What Most People Get Wrong About the Landing
There's a common misconception that Starship Flight 4 was just a "water landing" and therefore not a real landing. That's kinda missing the point.
The goal wasn't to recover the hardware. The goal was to hit a specific "virtual tower" in the ocean. Both the Super Heavy booster and the Starship upper stage had to perform a landing flip and a precision burn to zero velocity just above the waves.
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- The Booster (B11): It nailed it. It performed a soft splashdown in the Gulf of Mexico just seven minutes after launch. This paved the way for the incredible mid-air catch we saw in Flight 5.
- The Ship (S29): Even with a mangled flap and missing heat shield tiles, it performed its landing flip in the Indian Ocean. It hit the water vertically and softly.
Basically, if there had been a solid landing pad or a pair of "chopstick" arms waiting in the Indian Ocean that day, the ship might have survived. It proved that the math worked.
The Heat Shield Struggle
The heat shield is Starship's Achilles' heel. It's covered in about 18,000 hexagonal ceramic tiles. On Starship Flight 4, many of these tiles either fell off during the vibration of launch or cracked under the stress of re-entry.
SpaceX actually experimented on this flight. They intentionally left two tiles off and replaced another with a "thin" version just to see what would happen to the steel underneath. The data they gathered here led to the total redesign of the thermal protection system for Flight 5, where they added a secondary ablative layer (basically a backup heat shield) under the tiles.
Why It Still Matters for Artemis
NASA is banking on this rocket for the Artemis III mission to put humans back on the moon. Without the success of Starship Flight 4, that timeline would be dead in the water.
The FAA was watching this flight like a hawk. Because the mission didn't result in a "mishap" (meaning no public property was damaged and the ship followed its intended path), SpaceX was able to skip the months-long investigations that usually follow a crash. This accelerated the pace for the rest of 2024 and 2025.
Key Stats from the Mission
- Launch Time: 7:50 a.m. CT, June 6, 2024.
- Booster Engines: 32 out of 33 Raptor engines stayed lit during ascent (one shut down early, but the rocket compensated).
- Max Altitude: Roughly 211 km.
- Total Duration: 1 hour and 6 minutes.
The Reality of "Failure" in Space
In traditional aerospace, seeing a wing melt off is a catastrophe. In South Texas, it's just a Tuesday.
The "Last Ship" (at the time) showed that stainless steel—specifically the 300-series alloy SpaceX uses—is a bit of a miracle material. It has a high melting point, but more importantly, it stays strong at cryogenic temperatures and doesn't get brittle. If Starship were made of carbon fiber or aluminum like most rockets, that flap would have snapped off in seconds, and the ship would have tumbled and disintegrated.
Actionable Takeaways for Following Future Launches
If you're tracking the progress toward the moon, don't just look at whether the ship explodes. Look at these specific markers during the next flight:
- Tile Integrity: Check the "belly" of the ship during the live feed. If the tiles look uniform and aren't shedding, the new adhesive is working.
- Flap Hinge Protection: Notice the "taco" shaped covers on the flap joints. SpaceX redesigned these after Flight 4 to prevent plasma from leaking into the delicate machinery.
- Engine Relight: Watch for the transition from the coast phase to the landing flip. This is the highest-risk part of the entire mission.
The lesson from Starship Flight 4 is pretty simple: you don't need a perfect flight to have a successful mission. You just need to survive long enough to tell the computer what went wrong. The data from that melting flap is currently being built into the ships that will eventually land on Mars.
To stay updated on the current hardware at Starbase, you can check the live cameras at Boca Chica, which track the assembly of the newer "Block 2" ships that feature moved forward flaps—a direct design change resulting from the heat damage seen on this very flight.