Boom’s XB-1 Becomes First Civil Aircraft to Go Supersonic

Flown by Boom Chief Test Pilot Tristan “Geppetto” Brandenburg, XB-1 entered the supersonic corridor and reached an altitude of 35,290 feet before accelerating to Mach 1.122.

Boom’s XB-1 Becomes First Civil Aircraft to Go Supersonic

Flown by Boom Chief Test Pilot Tristan “Geppetto” Brandenburg, XB-1 entered the supersonic corridor and reached an altitude of 35,290 feet before accelerating to Mach 1.122 (652 KTAS or 750 mph)—breaking the sound barrier for the first time. For the first time since Concorde was retired in 2003, a commercial-type aircraft, the XB-1, went supersonic, touching Mach 1.1 three times during its one-half-hour test flight out of California’s Mojave Air And Space Port.

The XB-1 first flew in March 2024, with 10 more tests under its belt since – until today. The fastest of those previous flights was Mach .95, earlier this month. Boom Supersonic is now the first independent company to break the sound barrier with an aircraft intended for civilian use. (The Concorde was created in agreement with the U.K. and French governments, while the Tupolev Tu-44 was designed and manufactured with support from the Soviet government.)

Boom Technology, a U.S. company that developed XB-1, is building a bigger aircraft, Overture, a 64- to 80-seat affair (Concorde had 100 seats), for commercial operations. It says Overture will approach Mach 1.7 and should be ready in a few years. Airlines that have expressed interest include American, Japan Airlines and United. In the meantime, as with Concorde, the XB-1 test model can’t fly supersonic over land in the U.S. because of the powerful sonic boom. Today’s test over land was specially-sanctioned by the FAA.

Overture’s goal is to have a quieter sonic boom footprint and therefore might be able to fly over land as well as water, says a Boom spokesperson. The XB-1 has a curved shape and downward-curving nose to reduce wave drag and airflow, thereby keeping it stable and preventing damage.

Supersonic Speed

Supersonic speed is the speed of an object that exceeds the speed of sound (Mach 1). For objects traveling in dry air of a temperature of 20 °C (68 °F) at sea level, this speed is approximately 343.2 m/s.

Hypersonic Speed

Speeds greater than five times the speed of sound (Mach 5) are often referred to as hypersonic.