FAA Proposes Noise Rule for Supersonic Flight Over Land

The FAA has proposed replacing its decades-old ban on civil supersonic flight over land with a noise limit, allowing aircraft to fly faster than Mach 1 over the U.S. as long as the sonic boom they produce does not reach the ground above a set threshold.

Under the notice of proposed rulemaking that FAA Administrator Bryan Bedford signed on Tuesday, operators could fly supersonically without a special authorization if sonic boom overpressure at the surface stays no higher than 0.11 pounds per square foot. That performance-based standard would replace the speed-based prohibition the FAA enacted in 1973.

Initial supersonic operations would rely on a technique known as Mach cutoff, in which an aircraft’s speed and altitude, combined with atmospheric conditions, refract the sonic boom upward so it bends back into the atmosphere instead of striking the ground. Agency officials cited Boom Supersonic’s February 2025 “boomless cruise” demonstration and NASA flight research as evidence the approach works.

This proposed rule covers only en-route cruise noise. Separate landing and takeoff standards, which the FAA plans to propose later this year, would still be needed before manufacturers could certify a supersonic airliner. The FAA aims to finalize both rules by mid-2027.

Executive Order 14304, signed in June 2025, set the rulemaking in motion, directing the FAA to lift the overland ban. In March, the House passed the Supersonic Aviation Modernization Act, which directs the FAA to allow overland supersonic flights that do not produce a boom at the surface. That bill awaits Senate action.

The FAA has issued special flight authorizations for supersonic test flights to Boom Supersonic for the XB-1 demonstrator in 2024 and to Hermeus for the Quarterhorse Mk 2.1 this year.