The updated version of Honeywell's T55 turboshaft engine is in the final stages of development, the company reported this week. The updated engine produces more horsepower, range, and useful load and is expected to demonstrate improvements in reliability and availability while cutting fuel burn and operating costs.
"Our improvements come from new technology infused into the compressor section of the engine,” said John Russo, Honeywell Aerospace senior product director of military turboshaft engines.
Initial projections are that the updated engine is expected to deliver 25 percent more power, increasing shp from 4,700 to 6,000, while reducing specific fuel consumption by 8 percent. Honeywell said the improved T55 can be added as a kit to existing engines via overhaul or added as a new production, forward-fit option.
The legacy T55 engine currently powers the U.S. Army’s CH-47 Chinook-series of tandem-rotor helicopters and is flying in the Boeing-Sikorsky SB-1 Defiant Future Vertical Lift (FVL) demonstration aircraft. As currently envisioned, FVL will comprise a family of five military helicopters for the U.S. military that share common hardware, avionics, and engines.
"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 said.
The T55 was originally developed by Lycoming in the 1950s and its core was used in that company’s ALF 502 turbofan that powered early Challenger 600-series business jets and British Aerospace's BAE/Avro-146 four-engine regional jet. More than 4,200 T55s have been produced.