NEW YEAR. NEW SHIP. NEWLESSONS.
The seventh flight test of Starship and Super Heavy flew with ambitious goals, aiming to successfully repeat the core
capability of returning and catching a booster while launching an upgraded design of the upper stage. While not every
test objective was completed, the lessons learned will roll directly into future vehicles to make them more capable as
Starship advances toward full and rapid reuse.
On January 16, 2025, Starship successfully lifted off at 4:37 p.m. CT from Starbase in Texas. At launch, all 33 Raptor
engines on the Super Heavy booster started up successfully and completed a full duration burn during ascent. After
powering down all but the three center engines on Super Heavy, Starship ignited all six of its Raptor engines to separate
in a hot-staging maneuver and continue its ascent to space.
Following stage separation, Super Heavy initiated its boostback burn to propel the rocket toward its intended landing
location. It successfully lit 12 of the 13 engines commanded to start, with a single Raptor on the middle ring safely
aborting on startup due to a low-power condition in the igniter system. Raptor engines on upcoming flights have a preplanned
igniter upgrade to mitigate this issue. The boostback burn was completed successfully and sent Super Heavy
back to the launch site for catch.
The booster successfully relit all 13 planned middle ring and center Raptor engines for its landing burn, including the
engine that did not relight for boostback burn. The landing burn slowed the booster down and maneuvered it to the
launch and catch tower arms at Starbase, resulting in the second ever successful catch of Super Heavy.
After vehicle separation, Starship’s six second stage Raptor engines powered the vehicle along its expected trajectory.
Approximately two minutes into its burn, a flash was observed in the aft section of the vehicle near one of the Raptor
vacuum engines. This aft section, commonly referred to as the attic, is an unpressurized area between the bottom of the
liquid oxygen tank and the aft heatshield. Sensors in the attic detected a pressure rise indicative of a leak after the flash
was seen.
Roughly two minutes later, another flash was observed followed by sustained fires in the attic. These eventually caused
all but one of Starship’s engines to execute controlled shut down sequences and ultimately led to a loss of
communication with the ship. Telemetry from the vehicle was last received just over eight minutes and 20 seconds into
flight.
Contact with Starship was lost prior to triggering any destruct rules for its Autonomous Flight Safety System, which
was fully healthy when communication was lost. The vehicle was observed to break apart approximately three minutes
after loss of contact during descent. Post-flight analysis indicates that the safety system did trigger autonomously, and
breakup occurred within Flight Termination System expectations.
The most probable root cause for the loss of ship was identified as a harmonic response several times stronger in flight
than had been seen during testing, which led to increased stress on hardware in the propulsion system. The subsequent
propellant leaks exceeded the venting capability of the ship’s attic area and resulted in sustained fires.
Immediately following the anomaly, the pre-coordinated response plan developed by SpaceX, the FAA, and ATO (air
traffic control) went into effect. All debris came down within the pre-planned Debris Response Area, and there were no
hazardous materials present in the debris and no significant impacts expected to occur to marine species or water
quality. SpaceX reached out immediately to the government of Turks and Caicos and worked with them and the United
Kingdom to coordinate recovery and cleanup efforts. While an early end to the flight test is never a desired outcome, the
measures put in place ahead of launch demonstrated their ability to keep the public safe.
SpaceX led the investigation efforts with oversight from the FAA and participation from NASA, the National
Transportation Safety Board, and the U.S. Space Force. SpaceX is working with the FAA to either close the mishap
investigation or receive a flight safety determination, along with working on a license authorization to enable its next
flight of Starship.
As part of the investigation, an extended duration static fire was completed with the Starship flying on the eighth flight
test. The 60-second firing was used to test multiple engine thrust levels and three separate hardware configurations in
the Raptor vacuum engine feedlines to recreate and address the harmonic response seen during Flight 7. Findings from
the static fire informed hardware changes to the fuel feedlines to vacuum engines, adjustments to propellant
temperatures, and a new operating thrust target that will be used on the upcoming flight test.
To address flammability potential in the attic section on Starship, additional vents and a new purge system utilizing
gaseous nitrogen are being added to the current generation of ships to make the area more robust to propellant leakage.
Future upgrades to Starship will introduce the Raptor 3 engine, reducing the attic volume and eliminating the majority
of joints that can leak into this volume.
Starship’s seventh flight test was a reminder that developmental progress is not always linear, and putting flight
hardware in a flight environment is the fastest way to demonstrate how thousands of distinct parts come together to
reach space. Upcoming flights will continue to target ambitious goals in the pursuit of full and rapid reusability.
