Starship
SpaceX has been ordered to implement 63 corrective actions to resume flight testing of its Starship Super Heavy launch system following a debut liftoff mishap that left the launchpad deck foundation shattered.
The Super Heavy booster also failed in flight, triggering the rocket’s automated flight-termination system, which did not activate immediately to break up the wayward vehicle. The launch took place on April 20 at SpaceX’s Starship base of operations in Boca Chica Beach, Texas.
The FAA, which oversees commercial spaceflight by U.S. companies, said on Sept. 8 that it had completed its review of the SpaceX-led mishap investigation and ordered 63 corrective actions.
“These included actions to address redesigns of vehicle hardware to prevent leaks and fires, redesign of the launchpad to increase its robustness, incorporation of additional reviews in the design process, additional analysis and testing of safety-critical systems and components including the Autonomous Flight Safety System (AFSS), and the application of additional change control practices,” the FAA says in a letter to SpaceX dated Sept. 7.
In addition to meeting the FAA’s requirements, SpaceX is facing a lawsuit filed by environmental groups after widespread debris blanketed some of the surrounding communities during the launch.
“The FAA’s closure of the mishap investigation does not predetermine the results of any ongoing or future environmental reviews associated with Starship operations at Boca Chica,” writes Marcus Ward, the FAA’s Safety Assurance Division manager, in the letter to SpaceX.
In a Sept. 8 update on its website, SpaceX says during ascent, the vehicle sustained fires from leaking propellant in the aft end of the Super Heavy booster, which eventually severed connection with the vehicle’s primary flight computer.
“This led to a loss of communications to the majority of booster engines and, ultimately, control of the vehicle. SpaceX since has implemented leak mitigations and improved testing on both engine and booster hardware. As an additional corrective action, SpaceX has significantly expanded Super Heavy’s preexisting fire-suppression system in order to mitigate against future engine bay fires,” the company says.
To address the AFSS delay, SpaceX says it has enhanced and requalified the system to improve reliability.
Unrelated to issues from the first flight, the company says it is implementing system-performance upgrades such as a hot-stage separation system. It is designed to have the Starship’s second-stage engines ignite while the Super Heavy core stage is still firing, to push the ship away from the booster.
The company is also introducing a fully electric thrust-vector control system for the Super Heavy Raptor engines. The system has “fewer potential points of failure and is significantly more energy efficient than traditional hydraulic systems,” SpaceX says.
SpaceX has already rebuilt and tested an upgraded orbital launch mount-and-pad system that includes reinforcements to the pad foundation and the addition of a flame deflector.
“We learned a tremendous amount about the vehicle and ground systems during Starship’s first flight test,” SpaceX says. “Recursive improvement is essential as we work to build a fully reusable launch system capable of carrying satellites, payloads, crew and cargo to a variety of orbits and Earth, lunar or Martian landing sites.”
