Investigation Concludes on Flight 2 Mishap as SpaceX Prepares for Upcoming WDR

SpaceX Reassesses and Prepares for Next Starship Launch

After the mishap investigation into the second flight of Starship was officially closed by the Federal Aviation Administration (FAA), SpaceX is now focusing on restacking Booster 10 and Ship 28 onto the Orbital Launch Mount (OLM) for another Wet Dress Rehearsal (WDR) attempt. This WDR attempt will set the stage for a March launch attempt.

Ship 28, which completed a spin prime test to verify engine connection integrity, has been removed from Suborbital Pad B. On the same day, Booster 10 was rolled out to the OLM and placed onto the pad, indicating that SpaceX could be ready for another WDR attempt as early as next week.

The purpose of the WDR is to gather data on propellant loading efficiency, with the aim of reducing loading time. Successful completion of the WDR will provide the FAA with the necessary data to approve a license modification. If all goes well during the WDR, only one final stack will be needed for Flight 3.

In a statement issued by the FAA, it was confirmed that the mishap investigation into Starship Flight 3 has been completed and closed. The investigation resulted in 17 separate corrective actions for SpaceX to undertake, based on the findings from Booster 9 and Ship 25 flight.

For Ship 25, a leak developed during a planned Liquid Oxygen (LOX) dump towards the end of the burn, leading to ignition and fires onboard in the engine section. This LOX dump was part of the mission plan to gather data on future payload missions. The fire severed the wiring to the flight computers, resulting in loss of control and activation of the Flight Termination System (FTS).

To address these issues, SpaceX needs to make upgrades to robustness and reduce complexity for future ships. Ship 28 already incorporates additional stringers in the LOX tank to enhance robustness, as well as reduced vents for simplicity. Other changes involve improving hardware to prevent leaks, adding fire-resistant insulation to wiring, and rerouting wiring to safer locations.

Additionally, SpaceX plans to eliminate the LOX dump before engine cutoff to minimize failure risks. The company will also perform transient load analysis and modeling updates to better understand ship behavior during flight.

Booster 9 experienced a more complicated failure mode. When attempting to relight the middle ring of 10 engines, some engines shut down one after another until a single engine exploded, causing a chain reaction that led to the loss of the booster. The failure was likely due to a filter blockage on the inlet of the LOX turbopump.

To address this issue, SpaceX will redesign the tank filtration system. The company also intends to improve propellant slosh and update thrust vector control (TVC) modeling for better steering capabilities. Furthermore, SpaceX will reevaluate engine analyses and update engine control algorithms based on data from Flight 2 to enhance engine reliability.

Despite these setbacks, Starship Flight 2 was considered highly successful. The stack successfully reached stage separation and performed hot staging, a first for a vehicle of this size. Ship 25 achieved an altitude of 150 kilometers and a velocity of 24,000 kilometers per hour, coming close to orbital velocity.

It’s important to note that the completion of the mishap investigation does not grant SpaceX permission to fly Flight 3. The company must implement the corrective actions outlined by the FAA and await approval for a modification to the launch license.

As SpaceX continues to address the necessary improvements and learn from previous flights, the next chapter in Starship’s journey is eagerly anticipated. With each launch attempt, SpaceX takes another step towards achieving their goal of making space more accessible and furthering space exploration endeavors.