A pair of Honeywell T55 turboshaft engines successfully powered a new Future Vertical Lift demonstrator intended to modernize the U.S. Army Aviation branch. The engines lifted the Sikorsky-Boeing SB>1 DEFIANT medium-lift demonstrator on its first flight in late March.
Initial testing of the DEFIANT has been conducted with the current Honeywell T55 version used in the Chinook helicopter. However, the latest version of the T55 engine is in the final stages of development and will incorporate new technology to increase reliability, increase availability and save the U.S. Army operational costs.
“This is a new era for the T55 engine,” said John Russo, senior product director, Military Turboshaft Engines, Honeywell Aerospace. “Our improvements come from new technology infused into the compressor section of the engine that will reduce maintenance costs, increase aircraft readiness and lower the fuel burn — all while increasing the aircraft’s useful load and flight range.”
The T55 engine has been powering the U.S. Army’s Chinook helicopters for generations, but this latest variant in the series of engine modernizations positions the Army to take advantage of next-generation technologies while maintaining the support infrastructure it needs to move forward with its Future Vertical Lift platform. That platform will comprise a family of five military helicopters for the United States Armed Forces, all of which share common hardware such as sensors, avionics and engines.
While the focus of the latest T55 variant is on fuel savings, reliability and maintainability, the improvements also create a downstream result of greater horsepower. The new T55 engine can be incorporated by a kit at overhaul by either Honeywell or the Army Depot located in Corpus Christi, Texas. The latest configuration will also be available as a new production, forward-fit option.
Testing continues on the Sikorsky-Boeing SB>1 DEFIANT as the U.S. Army weighs a decision on its Future Vertical Lift platform. Honeywell is now poised to offer a common engine solution for both the Chinook and the aircraft selected by the Future Vertical Lift procurement team.
“This commonality will leverage all the Army’s existing support structure, and also bring the engine up to the latest certification standards to set a long-term growth path for airframe weight increases and power demands,” Russo added. “We want to congratulate the Sikorsky-Boeing team on reaching its first flight milestone, and we look forward to powering many more flights.”