Boom Supersonic is opening a new facility at the Colorado Air and Space Port to support ground tests of the Symphony engine it is developing for its planned Overture supersonic airliner.
Announcing the site selection on April 25, Boom said it would invest up to $5 million in the new facility this year to support testing of the Symphony’s prototype core—a 12-foot-long fixture containing the supersonic engine’s compressor, combustor, and turbine. In 2026, Boom aims to expand the facility to support full-scale tests of the medium-bypass turbofan engine.
Located approximately 30 miles east of Denver in Watkins, Colorado, Boom’s new engine testing facility was previously occupied by British aerospace group Reaction Engines, which used the space to develop hypersonic rocket engines before going out of business in late 2024.
“By leveraging an existing site, Boom will have the first independently-owned supersonic engine test facility for less than it would have cost to rent a government facility,” commented Boom founder and CEO Blake Scholl. “By vertically integrating propulsion, we are able to accelerate development, reduce costs, and custom-tailor an engine for Overture—unlocking capabilities like boomless cruise.”
Boom successfully demonstrated “boomless cruise” with a series of supersonic test flights of its XB-1 demonstrator aircraft earlier this year. That one-third-scale demonstrator, which is now retired, was powered by three GE J85 engines. The 80-passenger Overture will feature four Symphony engines and is designed to cruise at Mach 1.7.
According to Boom, the Symphony engine passed a key technical review last month, clearing the way for the company to begin manufacturing some engine parts. When scaled production begins, Boom partner StandardAero will test and assemble the engines at its facility in San Antonio, Texas. Boom will build the Overture airliners at a factory in Greensboro, North Carolina.
Boom aims to roll out the first Overture aircraft prototype in 2026 and begin flying it in 2027, and it hopes to complete FAA type certification by the end of the decade. The company holds orders and provisional sales agreements covering at least 130 Overture aircraft from customers including United Airlines, American Airlines, and Japan Airlines.