SpaceX has once again demonstrated the benefits of subjecting rocket hardware to real-world flight conditions. In its latest launch, the company achieved a significant milestone in its Starship flight test campaign by successfully returning both the booster and the upper stage to Earth through controlled ocean splashdowns.
The recovery of the Super Heavy booster and the upper stage, also called Starship, is critical to SpaceX’s long-term goal of making Starship the first fully reusable rocket. Successful recovery is the first step toward reusability, and SpaceX is showing that it can achieve this with Starship.
The ultimate aim is for both the Super Heavy booster and the Starship upper stage to fly back to Starbase, SpaceX’s private launch and development site in southeast Texas, and make vertical landings on solid ground. A controlled ocean splashdown is a preliminary step toward this objective. SpaceX, which pioneered reusing parts of rockets that have flown to space, currently achieves partial reusability with its Falcon 9 rocket, where the second stage is expended in orbit.
Starship launched from Starbase at 8:50 a.m. CT, marking the fourth flight in its test campaign. SpaceX plans to use the rocket for launching heavier versions of its Starlink satellites, delivering astronauts to the moon for NASA, and ultimately enabling multi-planetary life.
Despite being only the fourth launch of the massive Starship to orbit, the test proceeded smoothly. Only one of the 33 Raptor engines on the Super Heavy booster failed, and the company successfully executed its “hot-staging” stage separation technique. During hot staging, the engines on the upper stage ignite briefly while still attached to the booster, helping to push the booster away. SpaceX also jettisoned the “hot stage ring” between Starship and Super Heavy for the first time to reduce the booster’s weight on return.
Shortly after launch, the booster splashed down in the Gulf of Mexico. Over an hour later, Starship splashed down in the Indian Ocean, having survived the extreme heat from hypersonic atmospheric re-entry.
Super Heavy has splashed down in the Gulf of Mexico pic.twitter.com/hIY3Gkq57k
— SpaceX (@SpaceX) June 6, 2024
Engineers intentionally replaced one of the 18,000 heat shield tiles with a thinner version and removed two tiles to measure temperatures in those areas and test thermal protection options. Despite a damaged flap and losing many tiles, the ship successfully splashed down. SpaceX CEO Elon Musk noted that the heat shield system remains the biggest challenge in Starship’s development.
Starship has made significant progress since its first orbital test flight in April 2023, which ended in the mid-air explosion of both rocket parts and engine malfunctions. Each subsequent test has gone further, with Starship reaching orbit for the first time in the third test in March. That test also demonstrated key capabilities for delivering payloads to space, such as opening and closing the payload door.
