JayS wrote:

Yeah not too bright on the technical explanation of the differences.
AvWeek has been covering the competition and has had a series of articles over the last 6-8 months. This program is eventually aimed at $10 Billion / 6000 engines on the US side and many more engines for export and future applications (FVL). They had a chance to sit down with representatives from both GE and ATSC around April/May to go over their submissions and work so far.
GE Finalizing Proposal For ITEP After Design Review
NASHVILLE, Tennessee—The competitors vying for the U.S. Army’s Improved Turbine Engine Program (ITEP) are just months away from completing and submitting their final proposals.
GE Aviation and the Pratt & Whitney/Honeywell Advanced Turbine Engine Co. (ATEC) have developed rival engines—the T901 and T900, respectively—to replace GE’s T700 in the Army’s SikorskyUH-60M/V Black Hawk and Boeing AH-64E Apache. The winning engine potentially also could power the next generation of clean-sheet military rotorcraft in the lightweight category of Future Vertical Lift (FVL).
Ahead of the final submission, GE’s ITEP executives Ron Hutter and Mike Sousa say it is a tough competition against a “robust competitor.” But they are hopeful of emerging victorious when the service hands down its verdict later this year.
Hutter, GE’s T901 executive director, says the technical portion of the proposal based on a recent preliminary design review (PDR) will be submitted in June or July. The government’s source-selection decision is anticipated in the fourth quarter, followed by a contract award in the first quarter of 2019.
“We’re going to have to do our best to win this competition, but we’re certainly leaning forward to offer the best product we can,” Hutter says.
The two improved turbine engines, the T901 and T900, spawned from the Army’s Advanced Affordable Turbine Engine (AATE) science and technology effort. They have increased the power to 3,000 shp compared to the 2,000 shp T700 within the same volume while improving fuel consumption and engine life. As the program stands today, the ITEP winner could deliver as many as 6,000 brand-new engines to replace the T700s in the Army’s numerous Black Hawk and Apache fleets.
Both teams have produced two S&T demonstrator engines for the AATE program, but GE went a step farther by investing in a third prototype, which more closely aligned with the final design. That third engine (pictured) was powered up last year, and GE believes that investment buys down risk for the development phase, if it wins.
As the incumbent T700 manufacturer, GE has the most to lose in this race. Developed in the 1970s for the Black Hawk, the T700 turboshaft remains a lucrative franchise program, and the company expects to keep those engines humming for as long as the Army requires through refurbishment and upgrade.
GE has backed a “simple, proven” single-spool engine architecture that incorporates the latest technology from its military and commercial engine portfolios, such as three-dimensional aerodynamic design, ceramic matrix composites, additive manufacturing, advanced cooling and improved sand tolerance. ATEC has backed a two-spool architecture, which it claims is superior.
The increased power output afforded by ITEP will allow the Black Hawk and Apache, once re-engined, to operate at 6,000 ft. in hot, sandy environments (6K95) while carrying the necessary payload weight.
GE also has been in discussions with rotorcraft manufacturers about leveraging ITEP for Future Vertical Lift, specifically the Capability Set 1/FVL-Light armed scout procurement. GE believes it also could develop a more powerful ITEP derivative for the middleweight category, Capability Set 3/FVL-Medium, if required. “We all want to know where the FVL requirements land,” Hutter says. “We doubled the power of the T700 within the same volume and we could certainly incorporate that technology for FVL.”
Regardless of how the multiservice FVL procurement shakes out, GE says it is squarely focused on the main priority—re-engining the Black Hawk and Apache, which are underpowered in high and hot conditions because of weight gain. “Regardless of what happens with FVL, the Army is going to keep flying Black Hawks and Apaches for a long period of time, so we need to give them the best capability,” says Sousa, GE’s ITEP business development leader.
GE and ATEC are most of the way through their 24-month ITEP Technology Maturation and Risk-Reduction (TMRR) contracts, awarded by the Army in September 2016. As part of that effort, GE completed fit checks with the Black Hawk and Apache in December 2017 using a full-scale engine mockup. On March 2, it finalized the preliminary design review with the Army program office at Redstone Arsenal in Huntsville.
The competitors are now responding to a request for proposals issued in November 2017 for the engineering and manufacturing development phase, a two-step process. The non-technical portion of GE’s proposal—including cost, schedule and other details—was submitted in February, GE confirms. Following the PDR, the company is completing the final technical proposal. The TMRR phase will continue as the companies complete post-proposal activities and respond to any evaluation notices.
The winning engine will undergo 5,000 hr. of qualification testing during development. GE won’t say how many developmental engines it proposes to build, since that number is competition sensitive. It is expensive to build developmental engines, but having extra engines allows the winning company to burn through those 5,000 hr. of testing quicker. Flight tests in the Black Hawk and Apache will start once the chosen ITEP engine has completed extensive ground testing and is qualified for a preliminary flight rating.
ITEP To ACE: ATEC Going Full Throttle
As the Advanced Turbine Engine Company (ATEC) battles GE Aviation for the prized Improved Turbine Engine Program (ITEP), the joint venture between Honeywell and Pratt & Whitney is also heading into a preliminary design review on another next-generation U.S. Army engine initiative: the Alternate Concept Engine (ACE).
ATEC completed its preliminary design review for the T900 in early April and is now putting together its final “Phase 2” technical proposal for ITEP. Based on ATEC’s signature dual-spool turbine engine architecture, the T900 is challenging GE’s single-spool T901 in the 3,000 shp-class ITEP competition to re-engine thousands of Army Sikorsky H-60 Black Hawk and Boeing AH-64 Apache helicopters.
Spawned from the Army’s Advanced Affordable Turbine Engine science and technology demonstration, the Army awarded 24-month preliminary design contracts in late 2016 for both ATEC’s T900 (HPW3000) and GE’s T901 (GE3000). Only one team will advance beyond this technology maturation and risk-reduction phase and into full-scale development. The prize is a $10 billion program to deliver more than 6,200 engines to replace the 2,000-shp GE T700 in the Black Hawk and Apache.
Speaking to Aerospace DAILY at the Army Aviation Association of America’s annual symposium here on April 25, ATEC President Craig Madden and Vice President Jerry Wheeler said they are feeling confident heading into the downselection. The Army intends to make a contract award in the first quarter of 2019, probably around January 2019.
“A lot of very good work has been done over the last 18 months by the design team,” Wheeler says. “They had the opportunity to show the results of that work and talk about it during the preliminary design review. I think we did it to the Army’s satisfaction.”
He says the ITEP program has been consistently meeting its target milestone and remains Army Aviation’s No. 1 modernization priority, with strong backing on Capitol Hill.
“As long as we keep hitting those milestones, the capability this engine is going to bring sells itself,” Wheeler says. “We promote the program on Capitol Hill, and we’ve seen no naysayers. It’s got good support with everybody we brief.”
If selected, ATEC would roll straight into detailed design of the T900 over the first 12-18 months. Then it would begin building developmental hardware for rig testing, preliminary flight rating testing and eventually first flight in the Black Hawk and Apache. The Army intends to begin fielding ITEP engines around fiscal 2026.
“We feel good. We like our engine and our partnership: Honeywell and Pratt & Whitney,” Wheeler says. “We set out in 2006 to develop a better engine together than either of us would have done apart.”
“We had very good results during the science and technology phase and have done exceptionally well now during the preliminary design phase,” Madden says. “We should be able to win this.”
As work continues finalizing the T900 proposal, ATEC is gearing up for a preliminary design review on the ACE science and technology demonstration program, which it won in October 2016. The review with the Army is scheduled for this month.
The Army’s next technology demonstrator engine, ACE aims to validate a variable speed turbine design for an ITEP-class engine. Then components were first demonstrated on a laboratory test rig, but will now be proven on the back of ATEC’s HPW3000 prototypes.
The goal of ACE is to develop a variable speed turbine that throttles up or down depending on the speed of the main rotor.
Many of the next-generation rotorcraft concepts being proposed for the Army-led Future Vertical Lift program reduce their main rotor speeds considerably during cruise mode. But today’s engines maintain an almost constant speed that is less efficient during slow-rotor phases of flight. One solution is a variable speed power turbine. The other is a variable speed transmission. Or it could be a combination of both.
“Our component technology for a variable-speed powered engine was very successful,” Wheeler says. “We were able to demonstrate the operation of the powered turbine over a very wide speed range with a very good efficiency profile—essentially a flat efficiency profile. That’s what we’re looking to do in the engine development as well.
ATEC hopes to fully demonstrate ACE on the 3,000-shp-class HPW3000 in 2020/21. The company says it is in discussions with all the Future Vertical Lift platform manufacturers about supporting their propulsion needs, perhaps with an ITEP engine or a variable-speed derivative.