GE Aviation Delivers Improved Turbine Engine During U.S. Army Preliminary Design Review
Next-gen Apache, Black Hawk powerplants may leverage additive manufacturing, CMC, and advanced cooling technologies
An updated version of GE Aviation’s T901-GE-900 turboprop engine used in the AH-64 Apache attack and UH-60 Black Hawk utility helicopters successfully completed the preliminary design review (PDR) for the U.S. Army’s Improved Turbine Engine Program (ITEP). This marks a key step toward improving performance and efficiency and may also contribute to other U.S. Army goals, such as powering a potential scout-class helicopter.
The review is a key step in the adoption of a powerplant for use in real-life scenarios, with the full-scale T901 mockup demonstrating its fitment into both helicopters, thanks in part to GE Aviation’s production of the AH-64 and UH-60’s current T700 powerplant over the past several decades. The next step will involve the U.S. Army officials choosing between the T901 and a competing design from a partnership between Honeywell and Pratt & Whitney.
“The T901 is lighter, less complex and more maintainable for the warfighter, which leads to improved readiness and reduced life-cycle costs,” notes GE Aviation’s T901 Program Executive Director Ron Hutter.
The T901, which run in the in the 1,500- to 3,000-shaft horsepower class, incorporates additive manufacturing, 3D aerodynamic design tools, ceramic matrix composites (CMCs), advanced cooling technologies, and sand tolerant technologies. GE has spent decades developing and maturing these technologies in its commercial and military engines businesses.
Additive manufacturing allows GE to create advanced, cost effective parts at an accelerated rate that reduce fuel burn, decrease weight and increase durability. For example, the T901 includes an additive part that reduces an assembly of more than 50 subcomponents into one part.
To help increase additive manufacturing capacity for the T901 and related civilian programs, the GE Aviation has created a CMC-specific facility in Huntsville, Ala.
The Cessna Denali and T901 variants
The incorporation of 3-D printed parts in the T901 leverages investments in new production plants, equipment, and designs utilized for GE Aviation’s commercially-funded programs such as the Catalyst advanced turboprop engine for the Cessna Denali. The Catalyst engine is the world’s first turboprop engine with 3-D printed parts. A civilian turbine engine, the Catalyst, leverages similar technology and is also based on the existing T700 program. Like the T901, it includes variable stator vanes and 3D printed parts using additive manufacturing. It will run in the 850- to 1,600-shaft horsepower class. The Catalyst will also leverage a Full-Authority Digital Engine Control (FADEC). The automated system helps improve fuel efficiency by consistently adjusting fuel-air ratios and stator vane pitch. Company officials say it results in a 20 percent lower fuel burn and 10 percent higher cruise power over competitors.
Future vertical lift applications
In recent years, the U.S. Army has sought a replacement for the OH-58 Kiowa reconnaissance helicopter. Currently, the OH-58 only fulfills approximately 20 percent of U.S. Army reconnaissance needs—as compared to the AH-64 Apache, which fulfills approximately 80 percent.
The suitability of the AH-64 for these types of sorties is an open debate in the U.S. Army—it weighs nearly three times as much as the Kiowa’s 3,590 lbs. However, the AH-64 was designed as a heavy-weapons ground support platform with a 30-millimeter chain gun and hard-points for Hellfire missiles.
At the AUSA Global Force Symposium, Brigadier General Wally Rugen, head of the Army’s Cross Functional Team says that the cross-service future vertical lift platform is most likely to fill Capability Set 3, a medium-sized craft that would largely have the same mission set as the UH-60 Black Hawk.
Instead, they want something that can operate in large cities and control the operations of. Current proposals for the armed reconnaissance helicopter would either utilize one or two of the ITEP engines.