Aircraft

FAA clears the path for supersonic flight testing over US soil

FAA clears the path for supers...
The Aerion AS2 is designed to fly at speeds of up to Mach 1.4
The Aerion AS2 is designed to fly at speeds of up to Mach 1.4
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The Aerion AS2 is designed to fly at speeds of up to Mach 1.4
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The Aerion AS2 is designed to fly at speeds of up to Mach 1.4
Virgin Galactic's supersonic passenger jet concept has a delta-wing design
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Virgin Galactic's supersonic passenger jet concept has a delta-wing design

There's a new crop of supersonic aircraft beginning to sprout, thanks to advances in engine, materials and satellite weather tracking that will enable aircraft to break the sound barrier over land without the disruptive noise pollution of a sonic boom reaching the ground.

Aerion, Boom and Spike, for three examples, are working on supersonic business jets. Virgin Galactic is looking to bring the time savings of Mach 3 travel to a slightly broader passenger market. One of the issues, of course, is that supersonic flight has long been illegal over US soil, boomless cruise or no boomless cruise. But the US Government wants to set the regulatory agenda internationally, and has instructed the FAA to take a leadership role as the sector develops.

Supersonic flight over American soil will remain prohibited, but new regulations will streamline the process through which these companies can apply for specific exemptions, clearing away some of the red tape and offering a clear path for flight testing over land.

The FAA was clear in its Final Rule document that the new regulations will not allow supersonic flight in a categorical fashion, a result Boom in particular was pushing hard for; each test flight must be approved individually, including an analysis of the environmental impacts on the area over which it'll be undertaken. There were a number of objections to the ruling, chiefly focused on noise pollution but also questioning the environmental cost. The technology might improve, but physics is rigid; supersonic flight will always burn vastly more fuel than subsonic.

Virgin Galactic's supersonic passenger jet concept has a delta-wing design
Virgin Galactic's supersonic passenger jet concept has a delta-wing design

As we discussed in our interview with Aerion's Chief Sustainability Officer and Executive VP Environment & Sustainability, Gene Holloway, the hope is that eventually these new aircraft will use "caustic layers" of temperature inversion in the atmosphere to fly over Mach 1 but reflect the sonic boom back upward so it never touches the ground. The new regulations will now make noise testing an acceptable objective for test flights, allowing this boomless cruise technology to be evaluated over ground.

This will all still take some time. Aerion, for example, doesn't expect a first flight for its AS2 jet until sometime around 2025, and Virgin Galactic's effort is still in very early stages. Boom and Spike are closer, with small-scale demonstrator aircraft built, and in Spike's case, already flown. All these companies firmly believe that new technologies and approaches will bring supersonic flight back into the civilian sector in a fashion more sustainable than the Concorde, which took its final flight in 2003.

Source: FAA

7 comments
paul314
Is this a real rule, or just another midnight action by the outgoing administration?
Gazza
It would be interesting to see if SpaceX's Starship fly's reliably before these big players even start testing...
JDC1
It is a real rule and has been in place a long time. 1973 for civilian a/c. The current administration is loosening those rules to allow for testing of these jets.

As I recall from my military flying days the military has a couple of "supersonic test corridors." We are also authorized to exceed Mach 1 for national emergencies, like we did getting a/c to NYC on 9/11/2001.
Pancho Molina
Should be good to repeat the Concord sequence with current technology, with more flying models than wind tunnel conclusions.
Eddy
I thought the supersonic boom only happened once as the plane reached supersonic speed. Surely it is not continuous during flight, is it? Can't see it will be much of a problem as there will not be that many supersonic flights for the wealthy.
WB
any supersonic flight causes a continuous supersonic boom... as it flies overhead
Dan_of_Reason
I wouldn't be surprised if Elon Musk/SpaceX didn't have plans on the drawing board for a spacecraft that could put 24 or so people at a landing site anywhere on the planet in 45 minutes. Sure it may be as or more expensive than a Concorde flight, and there wouldn't be in-flight amenities, but it gets around the sonic boom issue.