Full speed ahead

Chris Kjelgaard reports on the effort and resources being poured into ITEP research and development by GE Aviation

An aircrew with the 1st Battalion, 147th Aviation Regiment, Wisconsin National Guard operate a UH-60 Black Hawk at Fort McCoy, Wisconsin during snowy winter conditions.

WHILE THE dust from the scuffe surrounding the US Army’s ITEP helicopter-engine competition hasn’t yet dissipated, the US Government Accountability Offce has cleared GE Aviation to proceed at full speed toward reaching the critical design review (CDR) stage of the $517 million ITEP engineering, manufacturing and development (EMD) contract the company was originally awarded in February.

After 12 years of developing technologies for its 3,000shpclass, single-spool T901-GE-900 offering for the US Army’s Improved Turbine Engine Programme (ITEP), culminating in its prototype T901 passing the US Army’s preliminary design review (PDR) in 2018, GE Aviation in February won the contest against the Advanced Turbine Engine Company (ATEC) for the sole-source ITEP EMD contract. In November 2017 the US Army Contracting Command had also awarded an ITEP PDR contract to ATEC – a joint venture between Pratt & Whitney and Honeywell – for that company’s two-spool T900 engine design, but in February it chose not to award ATEC an EMD contract, having all along indicated that the ITEP EMD contract would be awarded only to one contractor. So as things stand GE’s T901 is the ITEP engine.

However, ATEC refused to accept the US Army’s February decision and immediately filed a formal protest against the award. This promptly set in motion a 100-day review by the US Government Accountability Offce (GAO) of the US Army’s ITEP EMD contract-award process and its reasoning in reaching the award decision. Gambling that the GAO would overturn the decision reached by the US Army, ATEC wasn’t pleased on May 30 when instead the GAO told the two ITEP rivals that after a detailed review it was denying ATEC’s protest.

This immediately cleared the way for the US Army to rescind the stop-work order that ATEC’s protest had forced the US Army in February to issue to GE on the ITEP EMD contract. In fact, GE Aviation’s director of advanced turboshaft programmes and T901 programme manager Tom Champion told AIR International that the stop-work order “was rescinded within an hour of the GAO’s decision”.

Nevertheless, ATEC has continued to refuse to abandon the idea of potentially winning an ITEP EMD contract. On learning the GAO had denied ATEC’s protest, on May 30 ATEC president Craig Madden issued a statement which said: “The GAO findings notwithstanding, a procurement this crucial should never be made based on paper proposals. Indeed, it is customary for the Pentagon to thoroughly test competing engines before making a final down select. Testing provides clear, unequivocal evidence of engine capabilities that cannot be obtained through a proposal. Therefore, we have recommended that Congress provide the funding to allow the Army to take both engines further into the Engineering and Manufacturing Development phase of the procurement before making a final selection… the Army and Congress should ensure that the right decision is made for the warfighter. The best, lowest-risk, and most cost-effective way to do that is to compare the engines on the test stand.”

What the ITEP programme represents

The main reason ATEC is being a sore loser over the ITEP EMD award to GE is that the solesource contract is designed to lead to future production-contract awards, all of which would also be sole-source. This is important in dollar terms, because the US Army wants the production ITEP engine not only to replace the GE T700 engines (also single-spool) now powering all of the force’s UH-60 Black Hawk and AH-64 Apache helicopters, but also to power the Future Attack and Reconnaissance Aircraft (FARA) which represents Capability Set One of the Army’s wide-ranging Future Vertical Lift requirement. (The US Army reportedly requires approximately 400 FARA rotorcraft, but it hasn’t indicated yet whether it wants FARA to be a single-engine or a twin-engine aircraft.) As a result, not only will eventual production of the ITEP engine include some 6,000 T700 replacement engines and spares, but production will also encompass anywhere from 500 to 1,000 installed and spare FARA engines too.

Mike Sousa Jr, GE Aviation’s business development leader for advanced turboshaft programmes, said that even greater numbers of ITEP engines could eventually be produced. Like the GE T700, now in its 41st year of production as a turboshaft family and as its CT7 turboprop derivative, ITEP as a turboshaft or turboprop could be used to power other aircraft which either don’t exist yet or which eventually could need engine replacement. “We do think the T901 [as ITEP] will have other variants which will feed into the programme,” he said. “The base [production] case is for the US Army only, but other countries might be interested in re-engining their UH-60s and AH-64s.”

Additionally, “there could be other applications [for ITEP] in the future that are not being considered yet,” for the US Army or other operators of military helicopters or both, said Sousa.

GE Aviation’s T901 engine.
GE Aviation

Given the long-term potential for the ITEP engine to power a variety of rotorcraft types and also the considerable requirement that will exist for spare parts, spare engines and other aftermarket support over the course of what could be a 50-year-plus operational life, GE Aviation reckons a total programme dollar value of $20 billion would be a “modest” estimate. “We think this has kind of been a generational decision” by the US Army to develop and produce a major new militaryturboshaft engine, he said. “It’s a generation’s-worth of work… it’s a big part of our strategy and it’s very important to us.”

Any decision now by the US Congress to award ATEC a competing ITEP EMD contract could yet affect GE’s apparently rosy prospects for the T901 and the US Army’s ambitious timetable for getting the ITEP engine into service. (More on this later.) But whether or not the US Congress chooses to heed hard-lobbying ATEC’s clarion call, nothing now prevents GE Aviation from racing ahead with T901 technology maturation, ground-testing and eventual flight-testing (to be conducted by the US Army with the support of Boeing, Sikorsky and GE Aviation) over the next 66 months.


As GE embarks on the 66-month EMD contract, “what we are doing right now is to begin the critical design phase leading to the critical design review [CDR] of the engine,” said T901 programme manager Champion. During the lead-up to the CDR – which will be conducted by the Redstone Arsenal, Huntsville, Alabama-based US Army Programme Executive Operations for Aviation, the agency overseeing the ITEP programme – GE will perform “a limited number of component tests”, said Champion. “A ton [of such tests] have already been done in the 12 years” since GE first embarked on T901 R&D after being contracted under the US Army’s pre-ITEP Advanced Affordable Turbine Engine (AATE) programme. (Subsequently GE completed a Technology Maturation & Risk Reduction or TMRR contract and three full engine tests for ITEP, with the 15-month PDR contract GE was awarded in November 2017 representing the most recent stage of ITEP R&D before its EMD contract award.)

Following the limited remaining component-test programme, “quite a significant amount of ground factory-testing [will be needed] to get the preliminary flight rating and the flight qualification rating” required for GE to be able to deliver engines to the US Army for flight-testing on the UH-60 and AH-64, said Champion. The US Army will conduct the flighttesting, with airframers Lockheed Martin/Sikorsky and Boeing and with GE as the engine manufacturer closely supporting the flight-test programme. GE will have from “5,000 to 6,000 hours of ground testing to do to get the preliminary flight rating and the qualification rating”, he added.

A prototype T901 engine.
GE Aviation

While development and factorytesting will require only “a handful of engines”, GE will need to deliver “teams of engines” to the US Army for the flight-test programme, said Sousa. Additionally, “the [US] Army has optional engines [allowed by the EMD contract] to use for flighttesting. We would expect some of those to go into FARA flight-testing,” should the US Army launch FARA development during the course of the ITEP EMD contract. “All told, we expect 25 engines or so to be built over the next five years.” Engineassembly and most ground-testing will be performed at GE Aviation’s facility in Lynn, Massachusetts, but some ground testing will take place near Cincinnati in GE’s Evendale, Ohio facility, where it has a test cell in which high-altitude performance can be evaluated.

Although the US Army originally envisaged the ITEP development process lasting until late 2025, last year GE committed to shorten the duration of the development and flight-testing effort by a year. This is reflected in the 66-month duration of the ITEP EMD contract, which – as a result of the 100-day hiatus imposed by ATEC’s protest of the contract award in February – will now lead to T901 development and flight-testing being completed by late 2024. In order to achieve that, “we are targeting to complete preliminary flight release by the end of 2022,” said Sousa. “That allows them to begin flight-testing the engine. We committed to accelerating that by a year.” The end-2022 date suggests the US Army expects ITEP flight-testing to take fully two years.

Two years might sound excessive given that most commercialaircraft flight-test programmes take not much more than 12 months. However, Sousa noted that “there are things in the [re-engined] helicopters that will be different” – particularly the fact that the T901 is controlled by a full authority digital engine control (FADEC) unitdeveloped by GE, whereas the T700 being replaced in the UH-60 and AH-64 has no digital engine controls. While GE will provide the FADEC unit for the T901, Boeing and Sikorsky will need to work closely with the US Army to develop suitable digital interfaces (not provided by GE) for the UH-60 and AH-64 so those helicopters’ controls can interface with the FADEC computer.

If all goes to the US Army’s plan, GE should receive a low-rate initial production (LRIP) contract award immediately afterwards. GE is unwilling to offer any estimate of the numbers of engines to be involved in the first LRIP contract, Sousa noting that “we expect a lot of things to change between now and then” in terms of the number of engines the US Army specifies. “But it will be typical to normal LRIP production.” After that, “there will be a slow ramp over two to three years and then [production] will ramp up to full rate.” Sousa confirms GE is expecting to reach full-rate ITEP production “round about 2027”.

The crew of a US Army AH-64 Apache helicopter from the 1st Combat Aviation Brigade, 1st Infantry Division, prepare their aircraft for take-off
Visual Information Specialist Pierre-Etienne Courtejoie/US Army

How Congress could hurt ITEP

If the US Congress is persuaded by ATEC’s continuing lobbying to award the P&W-Honeywell JV an ITEP EMD contract in parallel with the contract the US Army has already awarded GE, the US Army would be delayed by two years or more in making the ITEP engine available to its helicopter units in the field, according to Sousa.

The main reason for this is that, in awarding and administering competitive R&D contracts, the US Army must be seen to be providing “a level playing field” for all the contract competitors throughout the contract’s duration. In practice this means “making sure they don’t give somebody a competitive advantage by giving [contract] information to one competitor before the other,” said Champion. “That does not accelerate a programme.”

Even before the ITEP PDR contract competition against ATEC, during its previous AATE and ITEP TMRR contracts GE “did a huge amount of testing, to give the [US] Army a huge amount of data” to help the force into understanding what it wanted in terms of ITEP design and performance, said Champion. “It was incredible how thorough the Army was in poring over the data [to allow it] to make the best available decisions on the information we put to them.”

However, while the US Army knew exactly what it needed from any future ITEP engine in terms of performance, cost, reliability and maintainability, it could only share data with the ITEP competitors at a rate that would ensure a level playing field for the company whose design and development effort was moving at a slower pace. That competitor was ATEC, according to GE. As a result, where GE had taken only eight months from receiving the preliminary design review contract from the US Marine Corps for the T408 large-turboshaft engine powering the Sikorsky CH-53K to passing the PDR, the PDR contract for the US Army’s ITEP engine lasted 18 months.

“The [US] Army did a very thorough evaluation” of both GE’s and ATEC’s ITEP PDR offerings, said Sousa. Now, “if there was another [ITEP EMD] award and another competition, having that competition could delay getting that engine to the warfighter. It would impact the Army getting that capability to the field.”

GE Aviation’s T901-GE-900 engine.
GE Aviation

The ITEP PDR competition lasted 18 months as a result of the US Army having to drip-feed information to the slower competitor, according to Sousa. “If we had to repeat that” for a competitively run EMD contract process “and synchronise for a level playing field” which would force GE to slow down to let ATEC catch up, it would delay ITEP’s operational availability “I would guess by at least a couple of years,” he said. “There would also be a big impact on what the [US] Army and the taxpayer would have to spend.”