The team at Boom Supersonic are determining whether a 12th test flight of its XB-1 demonstrator is needed before undertaking its first attempt at breaking the speed barrier.
On January 10, 2025, XB-1 reached speeds of Mach 0.95 during a 44-minute flight over the Mojave Desert with Chief Test Pilot Tristan “Geppetto” Brandenburg at the controls.
The 11th XB-1 test flight also saw the aircraft climb to 29,481 feet as it closes in on supersonic speeds.
“The primary objective for Flight 11 was expanding dynamic pressure to 383 KEAS (knots equivalent airspeed)—a higher number than will be experienced during XB-1’s first supersonic flight. This is the highest dynamic pressure the aircraft will ever experience—pushing beyond the anticipated pressure the aircraft will experience at Mach 1.1,” said a spokesperson for Boom Supersonic.
According to Boom Supersonic dynamic pressure is essentially how hard the plane is pushing through the air and as the aircraft approaches Mach 1 this becomes a key factor.
“Dynamic pressure and Mach number work together to shape the aircraft’s performance. During flight testing, we carefully expand one parameter at a time—either Mach number or dynamic pressure—in order to ensure safe and precise performance. The relationship between these two numbers changes with altitude—the faster and lower you are, the higher the dynamic pressure, and vice versa,” the spokesperson explained.
The founder and CEO of Boom Supersonic, Blake Scholl, clearly enjoyed watching the latest test flight.
Posting a video, Scholl wrote: “When approaching the speed of sound, parts of the airflow become supersonic. We’d predicted shockwaves at Mach 0.95… and if you look carefully enough, there they are!!”
When approaching the speed of sound, parts of the airflow become supersonic. We'd predicted shockwaves at Mach 0.95… and if you look carefully enough, there they are!! pic.twitter.com/GCXKW5Q8Nm
— Blake Scholl 🛫 (@bscholl) January 10, 2025
The Boom Supersonic team will now need to decide whether another test flight is needed prior to taking XB-1 to supersonic speeds.
“We did have some GPS and radio issues. Team is contemplating one more subsonic flight to ring these out before we go boom,” Scholl wrote.
Boom supersonic will carry out a thorough data review of aircraft performance and handling qualities during the test. XB-1 is on track to break the sound barrier in early 2025.