Unable to source one from the main OEMs, Boom Supersonic is developing an engine for its Overture supersonic airliner on its own. Boom announced today that it has commissioned a 35.000 lbs-engine with a consortium that includes FTT, GE Additive, and StandardAero. And it still plans to have Overture certified at the end of this decade. Boom to source bespoke Overture engine from consortium.
Boom suffered a major setback in September when Rolls-Royce announced that it would not extend the collaboration that was initiated in July 2020. Rolls-Royce said that the commercial supersonic market is not a priority. Soon, other major engine manufacturers Pratt & Whitney, General Electric, Safran, and Honeywell said the same. This left Boom with no other option to go its own way if it wanted to keep the supersonic project alive, something that CEO Blake Scholl is very keen to do.
Boom is putting its future in the hands of FTT (Florida Turbine Technologies), like Rolls-Royce a Derby-based company that is part of Kratos Defense & Security Solutions. It is specialized in all aspects of turbomachinery but notably in cooling technologies, but also offers an approved supplier database for hardware manufacturing.
What makes FTT a key asset for Boom is its experience with military engines. Its engineers have worked on the Pratt & Whitney F119-PW-100 after-burning turbofan that powers the Lockheed Martin F-22 Raptor fighter and its descendant, the F135 used on the Lockheed Martin F-35 Lightning. Both are fifth-generation fighter engines.
The Symphony engine, as the powerplant has been named by Boom, shares the same power range as the F119, so 35.000 pounds. It is a twin-spool, medium bypass turbofan that uses no reheat or afterburner to reach its maximum speed of Mach 1.7. FTT’s knowledge comes in with the passively-cooled high-pressure turbine (HPT). The engine is designed for the use of 100-percent sustainable aviation fuel (SAF).
Boom doesn’t specify the bypass ratio, but from the artist’s impressions of the redesigned Overture that was unveiled during the Farnborough Airshow, the bypass seems limited. However, Boom claims to have designed an efficient axisymmetric air intake and a nozzle with a variable geometry to optimize the engine’s performance while significantly reducing noise. Scholl said in Farnborough that the Overture will make no more noise than a conventional jet aircraft.
At what stage FTT is with the design of the engine, isn’t known. But when it comes to producing it, Boom secured to support of GE Additive, formed as a business unit of General Electric. It produces 3D-printed parts that are used widely within GE’s engines as well as in other industries. According to the Boom press release, GE Additive will offer additive manufacturing consulting and technology “while looking for additional areas to potentially collaborate.”
Boom wants Symphony to be designed for easy maintenance, for which it has contracted StandardAero as a partner on the program. The MRO company with a global presence brings experience on board with the maintenance of jet-fighter engines as well as commercial and business aircraft and helicopters. Boom plans to certify the new engine under FAA and EASA Part 33 and fulfill Chapter 14 noise requirements.
Commissioning a bespoke engine is a challenging business. Boom hasn’t said how it is funding this investment, which comes on top of the development of Overture and building the production infrastructure. Scholl said earlier this year that ground break for its new facilities in Greensboro was to happen before the end of 2022, but Boom didn’t offer any updates about that today.
Designing, testing, and certifying the Symphony engine are other challenges. Yet, Scholl remains optimistic – as ever- that production of the first Overture will start in 2024, roll out will follow in 2026, the first flight in 2027, and certification in 2029. But remember that the XB-1 flight demonstrator is now years behind schedule and still has to make its maiden flight.
