A silent sonic boom for upcoming Overture airliner?
February 10, 2025
Breaking the sound barrier is generally considered to be a noisy business, with the sound caused from the ensuing shock waves often disruptive to those on the ground. This limited Concorde’s supersonic capacity (with the airliner prohibited from surpassing Mach 1 overland) and is of key concern to California-based Boom Supersonic, currently pursuing its Mach 1.7-capable ‘Overture’ . However, analysis conducted with Boom’s scaled demonstrator has revealed the upcoming airliner will be able to fly at speeds at up to Mach 1.3 without an audible boom.
Specialised microphone arrays “placed in strategic locations under the flight path” of last month’s inaugural supersonic XB-1 run confirmed no audible boom was heard on the ground during the aircraft’s three forays faster than the speed of sound. “This confirms what we’ve long believed: supersonic traffic can be affordable, sustainable, and friendly to those onboard and on the ground,” enthused Boom Supersonic CEO and founder Blake Scholl. “With this success, we’re bringing Boomless Cruise to Overture”.
As illustrated above, Boomless Cruise works on the principle (known as Mach cutoff) that shockwaves produced by the sonic boom refract in the atmosphere, thus never reaching the ground. For this to happen, the sound barrier must be broken at a sufficiently high altitude, with exact speeds varying on atmospheric conditions – in Overture’s case, above 30,000ft.
Based on data collected during XB-1’s three supersonic runs, Boom Supersonic predicts that Overture will be able to fly at speeds of up to Mach 1.3 without an audible boom, before speeding up to its top cruising speed of Mach 1.7 over water. However, rather than being restricted to its earlier plan of operating at Mach 0.94 over land, this new data “establishes the possibility of Overture travelling up to 50% faster than today’s jets over land without an audible boom,” revealed Boom Supersonic.
However, even with Overture built and certified, the company will still require regulatory approval to break the sound barrier without breaking the rules – with the FAA currently prohibiting all supersonic flights over land. “Boom Supersonic supports revising this regulation to allow for Boomless Cruise and to establish a certification pathway for future low-boom aircraft,” it concluded. Boom Supersonic hopes for Overture to be certified and operational before the end of the decade, with 130 orders already on its books.
