U.S. defense officials and industry partners are putting the final touches to plans for a new national military engine technology development program that, for the first time, will include completely integrated power generation and thermal management elements, in addition to advanced propulsion technology.
The U.S. Air Force Research Laboratory-led (AFRL) ATTAM (Advanced Turbine Technologies for Affordable Mission capabilities) initiative will target technology development for a range of next-generation small, medium and high-power turboshafts and combat engines. The inclusion of integrated power and thermal technology has been driven from the outset by the expected need for these future engines to support more electric systems, directed energy weapons and powerful sensors, as well as to increase the propulsive efficiency and power of the vehicles themselves.ATTAM targets technology for next-gen small, medium and high-power military engines
Integrates thermal management and power generation with propulsion for the first time
Tests technologies capable of handing megawatt-class electrical loads, such as laser weapons
Details of the new effort, which will succeed AFRL’s decade-old Versatile Affordable Advanced Turbine Engines (VAATE) program, are expected to be publicly released following the government-industry Turbine Engine Technology Symposium, which takes place Sept. 12-16 in Dayton, Ohio. The VAATE program—which will be best remembered for ushering in the era of adaptive or variable cycle technology for production engines—is due to finish in 2019. ATTAM could begin as early as 2017, representing a potential two-year overlap between the programs.
The evolution to a broader-based research effort with ATTAM follows the trajectory established when VAATE took over in 2005 from the first such national propulsion program, called Integrated High Performance Turbine Engine Technology (IHPTET). Launched in 1987, IHPTET for the first time gathered together government-supported research into turbine engine technologies aimed at doubling power-to-weight ratio. The effort, which was focused on “flange-to-flange” engine performance improvement, led to technology that was incorporated into the F119 and F135 engines used in the F-22 and F-35, respectively......
VAATE’s remit was broadened to encompass the entire propulsion system, from inlet to exhaust, and widened to include development of multi-use technologies for a range of engine types, civil and military. In contrast with IHPTET’s sole focus on performance, VAATE targeted a 10X improvement in affordability. At the time of the program’s launch, specific measurable technical goals were also identified for each class of engine, so that progress toward the overarching 10X affordability goal could be measured. For the large turbofan/turbojet class, these included a 200% increase in engine thrust-to-weight ratio, a 25% reduction in engine fuel consumption, and a 60% reduction in engine development, procurement, and life-cycle maintenance cost.
“With VAATE there were several specific program goals, many of which were met,” says Doug Blake, director of AFRL’s Aerospace Systems Directorate. “Some of those goals continue into ATTAM, and I’m talking about things such as range and endurance goals,” he says. “In addition, the ATTAM program takes VAATE to the next step, in that we are looking at more closely integrating the thermal management and power generation pieces as well. That program is in its formulation phase right now.”
