FAA Clears Firefly Alpha Rocket for Return to Flight
Investigation into April 29 Incident Closed
The FAA has cleared the Firefly Alpha rocket to return to flight following the Flight 6 mishap on April 29, 2025.
“At Firefly, technical challenges aren’t roadblocks — they’re catalysts.”
Jordi Paredes Garcia, Firefly Aerospace
According to the company website, a thorough investigation was conducted in conjunction with the FAA, while at the same time an Independent Review Board of multiple government agencies, customers, and industry experts was assembled. The findings confirmed Firefly’s flight safety system performed nominally through all phases of flight. Both Alpha stages landed safely in the Pacific Ocean and the launch posed no risk to public safety.
Alpha Flight 6 lifted off and ascended nominally through stage separation. Alpha’s first stage then experienced a rupture milliseconds after stage separation. The pressure wave hit Alpha’s second stage, leading to the loss of the engine’s nozzle extension and substantially reducing stage two thrust. The second stage was able to recover attitude control and continued to ascend to an altitude of 320 km (≈200 miles) until running out of propellant. The vehicle was three seconds short of achieving orbital velocity and five seconds short of the target payload deployment orbit.
The ground-based video, onboard telemetry, post-flight empirical testing and Computational Fluid Dynamics analysis corroborated excessive heat from Plume Induced Flow Separation as the most probable root cause of the mishap. Alpha Flight 6 flew a higher angle of attack than prior missions. Plume-induced flow separation intensified heat on the leeward side reducing structural margins, causing the booster to rupture from stage separation induced loads.
Fortunately, the corrective actions are straight forward: increase thermal protection system thickness on Stage 1 and reduce angle of attack during key phases of the flight. Corrective actions have already been implemented.
“At Firefly, technical challenges aren’t roadblocks — they’re catalysts,” said Jordi Paredes Garcia, Alpha Chief Engineer at Firefly Aerospace. “Each mission provides us more data and enables us to continuously improve. Following all the lessons learned and corrective actions implemented, we were able to further increase Alpha’s reliability. We are grateful to the FAA, our customers, and the independent review board for their continued support through this process.”
With FAA approval to return to flight and corrective actions implemented, Firefly is now working to determine the next available launch window for Alpha Flight 7.