Tag: Engines

The T901 has been developed as a successor to the T700 engine that currently powers the UH-60 and AH-64 and is scaled to fit inside the same engine compartment. Compared to the previous engine, the T901 offers 50 percent more power — which translates to a maximum of roughly 3,000 shaft horsepower — bringing a considerable advantage in terms of hot-and-high performance, which is otherwise a significant limiting factor for rotorcraft. The new engine is also intended to bring improved fuel efficiency. On top of this, more powerful engines should ensure that the Black Hawk and Apache can carry heavier loads over greater distances. This is a factor that would be of critical importance in a future conflict across the vast distances of the Asia-Pacific theater, in particular, where helicopters are already struggling for relevance, due to their limited endurance.

Meanwhile, a simpler design and fewer parts should translate into reduced life-cycle costs. As well as traditionally manufactured components, the T901 also makes use of more exotic production techniques, including additive manufacturing and ceramic matrix composites.

Once installed in the UH-60 and AH-64, the T901 promises to provide these aircraft with increased range, longer loiter time, and reduced maintenance and sustainment costs.

The Army first got its hands on the T901 in October 2023, when two flight test engines were delivered for the FARA competitive prototype effort — one of the service’s highest-profile aviation programs. Sikorsky integrated the T901 into its Raider X aircraft and conducted ground runs. However, FARA was canceled in early 2024, a decision that we discussed in detail at the time.

Nevertheless, ground runs in the Raider X reduced the risk involved in Black Hawk integration and testing. In June last year, the first two T901 flight test engines for the UH-60M were handed over to Sikorsky.

For both the UH-60 and AH-64, more power is fast becoming essential, with the latest versions of these helicopters operating at much greater weights than when they were first introduced, as they have increasingly added more avionics, sensors, and weapons.

Speaking about the plan to put T901 engines in the AH-64 specifically,  T.J. Jamison, Boeing’s business development director for the Apache and for the AH-6 Little Bird, told TWZ last November: “The ability to bring ITEP into the Apache … sets you up for room for growth, extended range, reach, and payloads.” The ability to accommodate the new engines is something that’s ingrained in the latest V6.5 configuration of the Apache, which first flew in October of 2023 and is now coming off the production line.

Although Boeing has received a developmental contract for the integration of the T901 into the Apache, the U.S. Army has decided to prioritize putting the new engine into the Black Hawk. In the meantime, Boeing is using some of its own funds to continue the design work to get the new engine into the Apache.

For the Apache specifically, Boeing is also working on other improvements to the propulsion system, which will complement the new engines. As you can read about here, they include the Improved Tail Rotor Blade (ITRB) and Improved Tail Rotor Drive System (ITRDS). The ITRB is primarily focused on sustainment, ensuring the tail rotor blades can be more easily repaired and maintained, including on the battlefield, while ITRDS ensures that more power and authority are delivered to the tail rotor, something that will truly come into its own once harnessed to the power of the T901.

Returning to the UH-60M, the T901 is a fundamental part of the broader vision for a modernized Black Hawk fleet.

Speaking about what ITEP will provide the workhorse helicopter, Hamid Salim, vice president of Army and Air Force Systems at Sikorsky, noted that the re-engined Black Hawk would be able to “travel farther on less fuel and with more troops and cargo.” Salim also pointed specifically to the T901 enabling the UH-60M to take on new and emerging missions, “such as deploying and managing launched effects.”

Launched effects, previously referred to as air-launched effects (ALEs), are a category of varied uncrewed systems that you can read more about here. The new launched effects terminology reflects the fact they might be launched from land or maritime platforms, as well as crewed and uncrewed aircraft. They are a growing area of interest for the Army in particular, not only for rotary-wing platforms.

As well as the new engines and launched effects, the central pillars of the modernized Black Hawk include a Modular Open Systems Approach/digital backbone, which is set to improve safety and mission readiness while reducing unscheduled maintenance. Sikorsky is also increasingly working to reduce pilot workload and increase safety by incorporating autonomous technology, meaning the future Black Hawk should be able to operate with or without any humans on board.

New engine offerings could make the H-60 series and the AH-64 even more attractive to other potential customers. Both are still very much in production and the prospect of much more power in the future will only boost export prospects for what are already leaders in their respective market segments.

For the U.S. Army, meanwhile, re-engining the Black Hawk and the Apache will also go some way toward ensuring these older designs can contribute, even to a limited degree, to what officials are already talking about in terms of a revolution in air assault operations — one that they expect will be heralded by the arrival of the Future Long-Range Assault Aircraft (FLRAA) tiltrotor.

An entirely new kind of aircraft, the Army expects FLRAA will provide it with a vastly improved set of speed, range, and survivability metrics.

In the past, TWZ has questioned how the Black Hawk and the Apache might be able to better keep pace with FLRAA’s obvious difference in speed and range. While new engines won’t offer performance comparable with FLRAA, they will, at the very least, provide a significant advance over what today’s Black Hawk and Apache are capable. At the same time they will help bridge the gap to FLRAA. And even after this new aircraft enters service and fills the flightlines of Army Airfields, the UH-60 and the AH-64 are slated to continue soldiering on.

Contact the author: thomas@thewarzone.com