Bell Textron has secured Phase 2 funding from the Defense Advanced Research Projects Agency to build an X-plane demonstrator under the Speed and Runway Independent Technologies program.
The Texas, USA-based company will complete design, construction, ground testing and certification of an X-plane demonstrator capable of cruising at 460mph to 518mph (741km/h to 833km/h) at relevant altitudes while retaining the ability to hover and use unprepared surfaces. The aircraft will feature Bell’s proprietary stop/fold rotor technology, which the company has been developing for over 10 years.
“Bell is honored to have been selected for the next phase of DARPA’s SPRINT program and is excited to demonstrate a brand-new aircraft with the first-ever stop/fold technology,” said Jason Hurst, senior vice president, engineering. “This is an achievement we’ve been working towards for over 10 years, as we’ve leveraged our nearly 90-year history of X-plane development to bring new technology to our warfighters.”
The Speed and Runway Independent Technologies (SPRINT) program aims to develop high-speed vertical takeoff and landing aircraft that can use conventional runways and maximize survivability and payload capability through jet takeoff and landing. The aircraft will also utilize vertical lift systems and wings to takeoff in 200ft to 400ft (61m to 122m), allowing short field, “austere”, or damaged runways to continue operations.
Bell completed conceptual and preliminary design efforts during Phase 1 of the program, including a wind tunnel test campaign with a scaled model in December at the National Institute for Aviation Research at Wichita State University, Kansas, USA. Phase 2 includes detailed design and build activities culminating in flight test during Phase 3.
The company has also demonstrated the folding rotor, integrated propulsion, and flight control technologies during sled tests at Holloman Air Force Base, New Mexico, USA in February 2024.
The company’s folding rotor design that converts horsepower into vertical lift thrust while producing lift without creating adverse downwash conditions. This design provides increased safety for ground operations and ground personnel.
Bell’s says the design combines increased stealth and agility through advanced propulsion and digital flight control technologies that minimize signature during cruise and terminal area operations.
