General Electric (GE) and Pratt & Whitney (P&W) have been selected for negotiations to build test beds of more fuel-efficient engines for military aircraft.
The adaptive engine technology development (AETD) programme, run by the Air Force Research Laboratory, will fund a test bed utilising new technologies, based off a conceptual ‘three-stream’ engine that allows higher air bypass, and thus greater fuel efficiency. The engine would be able to either divert the airflow to bypass or directly into the engine core for greater performance.
Both GE and P&W are in the process of building engine cores, with plans to complete the engines by 2017. GE already has its engine core on the test stand, while P&W expects to do so by November.
GE, P&W and competitor Rolls-Royce were selected in 2007 for similar hardware tests under the adaptive versatile engine technology (Advent) programme, but only GE and P&W have been selected to move to the AETD stage. A R-R Advent test engine is meanwhile being prepared for testing later in the year.
Military-grade performance at civilian-level fuel burn has long been considered a holy grail of the jet age. While military aircraft require very high performance under combat situations, much flight time is spent in leisurely cruise when high performance is not required. Allowing the aircraft to dramatically change its rate of fuel consumption could save up to 1.2 billion gallons, according to the US Air Force.