SpaceX’s lesson from last Starship flight? “We need to seal the tiles.”

Summary

"We're going to try to do that next year," Gerstenmaier said. "In 2026, that'll be the focus, to get large-scale propellant transfer. If we're going to leave Earth orbit, we're going to need propellant transfer." A view of a portion of Starship's heat shield, including three experimental metallic tiles. Each tile is about the size of a dinner plate. Credit: SpaceX Gerstenmaier also briefly mentioned the results of experiments with Starship's Super Heavy booster on the most recent test flight. On this flight, the booster splashed down in the Gulf of Mexico just off the Texas coastline after propelling Starship toward space. SpaceX used the flight to put the booster through higher stresses as it came back to Earth, guiding the rocket to a water landing in the Gulf instead of returning it to the launch pad for a catch by the tower's mechanical arms. "What we were doing there is we're looking at the angle of attack and looking at how well the booster could fly itself to understand how much ability we had to get it back to the tower in the future," Gerstenmaier said. SpaceX engineers noticed the booster's performance on descent in flight doesn't match predictions from computer models or wind tunnel tests. In ground experiments, the booster encounters unstable buffeting as it slows below the speed of sound. Based on those results, "[we] should not be able to do what we do with our maneuver coming back with a booster, but we've been able to essentially show through flight that we have more stability than either CFD (Computational Fluid Dynamics) or the wind tunnels show that we have," Gerstenmaier said. "So, the big question to the research community is, why are we seeing these differences?" he asked. "We had an inkling that it would be there, but we weren't 100 percent sure, and we were able to do that extremely well." Gerstenmaier suggested that's a question best posed to universities and government labs. Companies like SpaceX innovate fast, but once they find a workable...