Currently, all civil aircraft  flights are prohibited from operating above Mach one speeds over land in the United States. Aircraft companies seeking to advance the testing of civil supersonic aircraft require a special flight authorization (SFA) under 14 CFR § 91. 818 (“Special flight authorization to exceed Mach 1”) to flight test  the next generation of supersonic (speed) capable vehicles. Issuance of SFAs is considered a major federal action under the National Environmental Policy Act (NEPA). As a result, the FAA must complete an environmental review of SFA issuance in compliance with NEPA and other environmental laws and requirements (see FAA Order 1050.1F: Environmental Policies and Procedures).

The FAA publishes notice of SFA applications and the availability of accompanying environmental review documents in the Federal Register. The following applications have been received by the FAA and are undergoing review:  

• SFA for Boom Technology XB-1 Supersonic Test Flights
  • Granted Special Flight Authorization (SFA) to Exceed Mach 1 for Boom Technology (effective April 7, 2024)
  • Final Environmental Assessment for Boom Technology XB-1 Supersonic Test Flights from the Mojave Air and Space Port, Mojave CA
  • Boom EA Final Finding of No Significant Impact for Boom Technology XB-1 Supersonic Test Flights

For further information, please email 9-APL-AEE-NEPA-Comments@faa.gov.