SpaceX redesigns Starship's grid fins to improve stability, control

SpaceX has redesigned the grid fins on its Super Heavy booster, part of the Starship system destined for Mars, to enhance stability and control during descent. The new design replaces four smaller fins and a landing fin with three larger, 50% bigger and stronger grid fins featuring a honeycomb-like structure. These fins, among the largest aerodynamic control surfaces ever built for a rocket, enable the booster to descend at steeper angles with improved maneuverability. The fins are also repositioned lower on the booster to align with the launch tower’s catch arms, allowing the rocket to be caught directly during landing—eliminating the need for a landing pad—and to protect the fins from engine heat. Internal components like the fin shafts are now housed inside the main fuel tank for added protection. This redesign follows recent test flight failures, including a May incident where the Super Heavy booster crashed into the Gulf of Mexico after failing to return to the launchpad, and a June explosion of the upper stage during ground testing.