Originally appeared on GEaerospace.com: https://www.geaerospace.com/news/articles/defense-engines-product-technology-performance/us-army-helicopters-have-tougher-missions
It’s not quite dawn and already hot. You’re at the controls of an U.S. Army helicopter, ferrying a dozen troops and a couple days’ worth of equipment to a drop-off point at a dry, dusty creek bed. On course over the mountains, while your hands work the controls and your feet the pedals, you’re constantly calculating. How much power can the engine pull at this altitude, this temperature, this weight?
“It takes a lot of awareness and coordination to fly these aircraft,” says Joe Snoke, who has piloted and managed the United States Army’s primary transport helicopter, the Sikorsky UH-60 Black Hawk, in missions ranging from flood rescues in Kentucky to convoy security in Afghanistan. Snoke, who completed active duty in 2017, is now at GE Aerospace as a director and still flies for the National Guard. “We used to say it’s like you’re beating the air into submission.”
At the controls of a Black Hawk, while he monitors rotor RPM and does the mental math, Snoke has relied on GE Aerospace’s T700 turboshaft engine to bring the air to heel. The power plant to both the Black Hawk and the Army’s main attack helicopter, the Boeing AH-64 Apache, the T700 has proven itself in the world’s harshest environments. With more than 25,000 engines delivered to over 130 customers in some 50 countries, the T700/CT7 family of engines has surpassed 100 million flight hours over its four decades of service.
The T700 line has grown more powerful and reliable with each of its dozens of variants, incorporating technological advances for enhanced performance. But times — and missions — change. Army aviators are being asked to do much more today than they were even 10 years ago. In response, as part of an Army-sponsored competitive program, GE Aerospace developed a successor to the T700 that will give the U.S. Army’s fleet an advantage for decades to come. Based on the same design as the T700 but using a simpler construction and revolutionary materials, the T901 engine offers more power, longer range, and enhanced maneuverability to complete more demanding missions that cannot be executed today.
With the first T901 engine delivery for the Black Hawk just weeks away, though, the proposed budget for FY2025 would nearly halve the funding, slowing the T901 program.
“We are at a critical point in getting this engine and its capabilities into the field. Quite frankly, in the history of Army aviation right now, there is no more important capability to our Army aviators than the T901 engine,” says James Myles, the major general who led the United States Army’s Aviation and Missile Command at Redstone Arsenal in Alabama.
Myles served in units like the esteemed 160 Special Operations Aviation Regiment, better known as the Night Stalkers. “Slowing production of the T901 will impact our military and our allies across the world who fly these helicopters. The technology can’t deliver benefits if it isn’t in the field.”
Preparing for the Next Mission
As the world becomes more unpredictable, the Army’s mission is not getting any easier.
As a result, the Black Hawk and Apache helicopters have taken on an ever-growing list of needed capabilities — and an ever-heavier payload demand. Cockpits have been upgraded with digitized avionics that give pilots a more detailed picture of conditions in and around the aircraft, improving navigation and, ultimately, survivability. The tradeoff is that every new piece of equipment adds weight, and the accumulation is taxing engine power. The strain is exacerbated by the aerodynamics of the hot weather and high altitudes where Army aviators find themselves.
Improved Performance
To boost power, the T901 relies upon an improved compressor — the rotating blades that squeeze incoming air. The higher the air pressure is a critical part of increasing the power and efficiency of the engine. Thanks to the compressor’s aerodynamic design, the T901 delivers 50% more power than the T700.
In combat, additional power translates to a higher weight limit and better maneuverability, but it also helps keep Americans safe at home. The Black Hawk is a workhorse, routinely enlisted for domestic operations such as disaster response. For example, helicopters are an essential firefighting tool, capable of dousing flames in areas ground crews can’t reach. When outfitted with a T901, a Black Hawk flying to reach the top of the tree lines at the highest altitudes can carry 1,400 extra gallons, 28 percent more water per trip, compared to the current engine powering Black Hawks.
The T901 is also improved by the inclusion of 3D printed parts. Manufactured as one component without welded or bolted joints, they eliminate hundreds of possible failure points. Together with components made from ceramic matrix composites (CMCs), which are just as resilient as metal at a third the weight, they also boost the T901’s fuel efficiency by 25%, extending the helicopter’s range and the time it can loiter over a target or landing zone. The result is an engine with a 20% longer lifespan that performs reliably whether in extreme heat or at high altitudes compared to the current engine.
“To a pilot, that means everything,” Geoff Crawford, who flew Apache helicopters and now is the director of Army programs for GE Aerospace.
Staying on Track
At a time when the Army needs more capabilities, the reduced funding would slow getting the T901 and its benefits into the field. In more than 900 hours of testing, the T901 engine has continually met the Army’s performance requirements.
Since winning the Improved Turbine Engine Program competition in, GE Aerospace has invested over $670 million in T901 research and development, including $40 million in machines, equipment, and tooling in 2024 alone.
A slowdown also risks triggering an atrophy of expertise as engineers and technicians migrate to other projects. The T901 program supports approximately 1,000 jobs across 23 states at GE Aerospace and suppliers.
“Congress can keep the program on schedule by restoring the funding that was cut in the proposed budget,” Crawford says. “If we want to stay ahead of our adversaries, we’ve got to keep our aviators outfitted with the best capability. We owe it to them.”
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