The GE T901 engine was developed as part of the Improved Turbine Engine Program to replace the T700 engines used by U.S. Army’s UH-60s and the AH-64s, and was also expected to equip the now-cancelled Future Long-Range Attack Helicopter.
Sikorsky announced on Jan. 29, 2025 that it has tested the new General Electric GE T901 engine on a U.S. Army’s UH-60 Black Hawk during a ground test run at the company’s facilities in West Palm Beach, Florida. The test was conducted by a combined U.S. Army and industry test team and operated by Army and Sikorsky pilots, said the company.
The engine was developed as part of the Improved Turbine Engine Program (ITEP) to upgrade the service’s UH-60 and AH-64 Apache fleet with new, more fuel efficient, durable and powerful engines. The T901 engine was also meant for the now-cancelled Future Attack Reconnaissance Aircraft (FARA).
On both the helicopters, the T901 would replace the older T700 engine, producing 50% more power, 25% reduction in fuel consumption, in line with the U.S. military overall carbon reduction and emission goals. The T700 has logged more than 100 million flight hours over the last four decades.
We have light off!
For the first time, a UH-60M Black Hawk conducted ground runs equipped with two @GE_Aerospace T901 Improved Turbine Engines. pic.twitter.com/xqVV1ScQaE
— Sikorsky (@Sikorsky) January 29, 2025
The test
Beside an orange flight data probe, the test UH-60 also has orange-colored shrouds on both main rotor and tail rotor assemblies. Their purpose is not known, but it is possible they might contain sensors and recording devices to collect data on the rotors’ performance with the new engines.
Using the two T901s installed on the UH-60, the engine “demonstrated its capabilities through a series of rigorous procedures,” overseen by a combined team of U.S. Army, Sikorsky, GE Aerospace engineers and test pilots.
The video released by the company showed the initial engine startup (ignition), with the smoke billowing from the exhaust, with both the rotors eventually running after the gearbox has been engaged. The engine was tested in its “start-to-fly progression, including idle and fly modes and with the rotor brake disengaged,” Sikorsky said in a statement.
The start-to-fly progression tests the functionality of the entire system, from the engine start sequence to the engagement of the main rotor to enable lift-off. Both Sikorsky and GE Aerospace identified the testing areas pertaining to the fuel, electrical, hydraulic, engine bay flow, and flight control systems, besides acquiring test data from “engine instrumentation.” The successful ground test set the stage for more advanced testing, such as hover and forward flight tests.
The 3,000 shaft horsepower offering 50% more power would allow the helicopters to carry greater loads, across longer distances, a useful feature in a vast maritime battlespace of the western Pacific theater. The interest in saving on fuel cost has also been reflected in U.S. Air Force’s programs like the microvanes on C-17 Globemaster III aircraft and the Blended Wing-Body “Pathfinder” program.
Additionally, GE Aerospace has also made use of additive manufacturing and 3D printing, beside conventional machining and metal forging, to produce many of the T901’s components. This reduces life-cycle and maintenance costs, simplifying the supply chains. Additionally, the extra power would also be useful for the electronic warfare capabilities being packed onto the Apache, since the microelectronics and sensors need greater electrical supply.
Ground tested on FARA prototype Raider X first
Defense News quoted Sikorsky president Paul Lemmo in May 2024, who proposed using the ITEP engine in its FARA prototype, the Raider X, ahead of the installation into the UH-60 Black Hawk helicopter. At the time, the Army’s plan to replace all Black Hawk and Apache helicopter engines with ITEP power plants had been delayed owing to technical issues and supply chain disruptions following the COVID-19 pandemic.
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The U.S. Army received its first T901 engines for the FARA program in early-Oct. 2023. Sikorsky eventually tested the ITEP on its FARA prototype, the Raider X, in Apr. 2024 at its facility in West Palm Beach in Florida, with Lemmo saying it “performed well.”
“This is the first time it’s under a full load in a real aircraft turning rotors,” Lemmo said in the report. “We collected that data at low speed, we’re analyzing it and the Army’s authorized us to now run up to full speed on the ground to collect more data.”
📢 BIG NEWS! 📢
The @USARMY announced today the acceptance of the first #T901 engine for the service’s Future Attack Reconnaissance Aircraft.
We couldn’t be more proud to share in today’s significant milestone for the #USArmy!
More ➡️: https://t.co/AN8B6zAc1s#ArmyAviation pic.twitter.com/bmXv5UHiYD
— GE Aerospace (@GE_Aerospace) October 4, 2023
Tests of the ITEP so far were on test stands, but the ground run on the FARA’s Raider X generated valuable data for analysis. The engine itself was fitted into the Raider X without any issues. The ITEP was then scheduled to go into a Black Hawk later in 2024, which happened recently. Needless to say, those results gave valuable insights into the engine’s performance on the UH-60, besides drawing up a comprehensive testing plan.
During the 2024 edition of the Army Aviation Association of America in Apr. 2024, Brig. Gen. David Phillips, the program executive officer for aviation, said they planned to deliver two ITEP engines to Sikorsky by June of that year, mentioned another Defense News report. These were delivered by Jun. 27, 2024, with the service later authorizing Sikorsky to run the rotors at full speed.
While one engine was used to conduct the “fit check” in one of the two modified Black Hawk helicopters, the other one would conduct the actual ground runs and flight tests. At the time, Lemmo anticipated a timeline of six months from integration of the engine, to the ground runs and actual flight, with Phillips predicting 2025 for the first flight. This rough schedule appears to have broadly been followed.
