The Boom XB-1 demonstrator measures 71 feet long, or roughly a third of the length of the planned Overture supersonic airliner. (Photo: Boom Supersonic)

Boom Rolls Out XB-1 Demonstrator

The Colorado-based company plans for the eventual Overture airliner to make its first flight in 2025.

Boom Supersonic recently staged an online rollout ceremony for its one-third scale XB-1 demonstrator, scheduled to make its first flight sometime next year. Powered by three General Electric J85-15 turbofans, the composite-bodied XB-1 will fly up to Mach 2.2 ahead of the planned introduction of the Overture supersonic airliner, expected to make its own first flight in 2025.

Boom expects the XB-1 to demonstrate technologies planned for the 55-seat Overture, such as carbon-fiber composite construction, computer-optimized high-efficiency aerodynamics, and supersonic propulsion systems.

The design includes what Boom calls one of the highest-efficiency civil supersonic intakes ever tested. During the rollout, Boom CEO Blake Scholl explained the importance of the aircraft’s engine intakes, which slow the speed of the airflow to roughly half the speed of sound to accommodate the subsonic GE engines. Boom has worked for the last five years with Rolls-Royce on the planned medium-bypass turbofans for the Overture.

“Supersonic jet engines are all subsonic on the inside,” explained Scholl. “So the inlet is actually doing a lot of work. It’s taking supersonic air, slowing it, compressing it, and feeding it to the front of the engine at about half the speed of sound. And it has to do it really efficiently. We think we have one of the most efficient designs ever built.”

Boom plans to start building the Overture at a new, still-unidentified factory location in 2022 and ready the first production airplane for passenger service around 2029.

Scholl noted that while safety and sustainability account for two of the three pillars of the program, speed lies at its core. If successful, the Overture will fly from Tokyo to Seattle in four and a half hours, New York to London in three and a half hours, and Montreal to Paris in four hours.

Although Scholl didn’t deny that a market exists for a supersonic business jet, he said Boom’s focus centers solely on commercial service. “It goes back to the mission for our company,” he stressed. “And that is to make the planet dramatically more accessible by making aircraft that are faster, more affordable, and more convenient. So I think there is a place in the world for supersonic business jets, I don’t think they’re a priority for us because we get up every morning and say, ‘How do we make flight more affordable for more people?’ not ‘How do we build something we can charge more for?’” Boom estimates that passengers will fly on the Overture for 75 percent less than they did on the Concorde.

Boom has partnered with Flight Research, Inc. (FRI) on the flight test program. Plans call for incrementally expanding the envelope of the XB-1 to supersonic speeds. Ground and low-speed taxi testing will occur at Centennial Airport in Colorado, while high-speed taxi and flight take place at Mojave Air and Space Port in California.

Supersonic flights will carve a path over a supersonic corridor stretching across the Mojave Desert. FRI will provide a two-seat, twin-jet supersonic trainer to serve as a chase plane during the flight test program. Boom subleases part of FRI’s headquarters to support the XB-1 tests, including the development of a fully instrumented flight test control room and the use of one of the FRI hangars for reassembly and maintenance of the XB-1.

Planning to fly the XB-1 on sustainable alternative fuels, Boom promotes the program as 100 percent carbon-neutral. Boom last year formed a partnership with Prometheus Fuels for the supply of sustainable jet fuel during the XB-1 test program.