The AETP programme aimed to create two demonstrator engines to replace the F135-100 engines (F-35A and F-35C). The XA101 Enhanced Engine Package (EEP) engine was developed by Pratt & Whitney to compete with General Electric’s XA100 engine. The F-35 Lightning II Joint Programme Office (JPO) was expected to select one of the two engines in 2023.
The Pentagon will return to the engines used by the current
F-35. As such, the Adaptive Machine Transition Programme (AETP) was
discontinued. The AETP was initially intended to produce engines with greater
increased thrust and high efficiency. This decision means the US Military will
not proceed with its Adaptive Machinery Transition Programme. The adaptive
engine uses three airflows to cool the engine and has an adaptive cycle that
allows for increased thrust and fuel efficiency. General Electric Aviation and
Pratt & Whitney have participated in designing the new AETP engine, but
only General Electric Aviation has installed the engine, the XA100.