US regulators have finalised a rule intended to ease the process by which aircraft manufacturers obtain approvals to perform supersonic aircraft flight tests.
The move marks another step by the US Department of Transportation (DOT) and Federal Aviation Administration to support several companies working to bring a new generation of supersonic civil aircraft back to the world’s skies.
“Today’s action is a significant step toward reintroducing civil supersonic flight and demonstrates the department’s commitment to safe innovation,” says agency secretary Elaine Chao.
“This rule will help ensure that companies developing these aircraft clearly understand the process for gaining FAA approval to conduct flight testing, which is a key step in ultimately bringing their products to market,” adds the FAA, which sits under the DOT.
The new regulation aims to “streamline” how aircraft manufacturers apply for the “special flight authorisations”. They need those authorisations to flight test aircraft at supersonic speeds. The USA otherwise bans supersonic civil flight.
The rule specifies the information that manufacturers must include in flight-test applications. That information includes general details about the operator and the proposed operating area, and also the measures that operators will take to ensure “no measurable sonic boom… will reach the surface outside of the proposed flight area”, the rule says.
The FAA has been working to improve its supersonic flight rules since being ordered to do so under the FAA’s 2018 authorisation law.
As part of that effort, the FAA in April 2020 proposed a rule that seeks to set take-off and landing noise limits for supersonic aircraft. The noise rule has not been finalised.
Companies developing new civil supersonic aircraft include Aerion Supersonic, Boom Supersonic and Spike Aerospace. Engine makers GE Aviation and Rolls-Royce have been studying powerplants for new supersonic aircraft.