Honeywell engine to power Lockheed Martin Sikorsky-Boeing DEFIANT X

The HTS7500 turboshaft engine is the latest model in Honeywell’s family of military engines.


Lockheed Martin Sikorsky-Boeing

Sikorsky, a Lockheed Martin Co., and Boeing named Honeywell as the engine provider for DEFIANT X, the advanced helicopter for the U.S. Army’s Future Long-Range Assault Aircraft (FLRAA) competition.

The U.S. Army initiated FLRAA in 2019 to develop a new utility helicopter that will replace the Sikorsky UH-60 Black Hawk starting in 2030.

The DEFIANT X weapon system builds on the handling qualities and capabilities proven by the team’s technology demonstrator, SB>1 DEFIANT.

With Honeywell providing the HTS7500 turboshaft engine, Team DEFIANT brings Army Aviation experience to FLRAA while integrating with legacy platforms and existing infrastructure.

The HTS7500 turboshaft engine is the newest and most technologically advanced model in Honeywell’s family of military engines, which includes the T55 engine that has powered the H-47 fleet for more than 60 years. Like the T55, the HTS7500 is designed to thrive in austere environments. The HTS7500 exceeds mission power and fuel consumption requirements.

Powered by a pair of HTS7500 engines, the DEFIANT X can fly 2x faster and farther than the Black Hawk and is currently being tested in a digital combat environment, where it continues to prove itself for mission requirements.

The new engine comes equipped with a modernized control system, which enables a highly secure flow of engine data. The control system improves operating capabilities, reduces life-cycle costs, and ensures engine health status through its digital thread road map.

“This engine builds upon the battle-proven architecture of the T55,” said Dave Marinick, president, Engines and Power Systems, Honeywell Aerospace. “The engine is structurally similar, which is great for maintainers in the field because they can use current tools and training. However, when it comes to performance, the HTS7500 is 42% more powerful than the T55-GA-714A and has the lowest total weight compared to other engines in its horsepower class.”

“Team DEFIANT’s strength is built on the experience of Sikorsky and Boeing, and a commitment to Army Aviation,” said Mark Cherry, vice president and general manager of Boeing Vertical Lift. “Honeywell’s history with Boeing and the U.S. Army makes us even more confident that DEFIANT X is the best fit for the Army’s total mission.”

“DEFIANT X is a transformational aircraft, and Honeywell is giving us a transformational engine to power it,” said Paul Lemmo, president of Sikorsky.

“Honeywell is excited to be a part of Team DEFIANT and proud to play a part in the future of vertical lift for the U.S. Army,” said Ricky Freeman, president, Defense & Space at Honeywell Aerospace. “We’re confident our HTS7500 engine on the DEFIANT X platform will provide the Army with an agile, fast and maneuverable platform that will help ensure overmatch capability in the future battlespace.”

Together, Sikorsky and Boeing have built 90% of the U.S. Army’s current military rotorcraft and have totaled more than 15 million flight hours. Sikorsky-Boeing submitted the proposal for DEFIANT X for the U.S. Army’s FLRAA in September 2021. Contract award is expected this year.

HTS7500 turboshaft engine at a glance

• Combat-proven engine architecture

• Demonstrated sand ingestion tolerance

• 42% power improvement (compared to T55-714A)

• 18% reduction in specific fuel consumption (compared to T55-714A)

• Commonality with already fielded U.S. Army hardware