The U.S. Air Force has decided to move forward on Raytheon Technologies‘ Pratt & Whitney Engine Core Upgrade (ECU) for the F-35 fighter and end the service’s Advanced Engine Transition Program (AETP), which received the Air Force-requested amount of $286 million last year.

The Air Force’s fiscal 2024 budget requests $245 million for ECU and increases research and development funding for an advanced engine for the Next Generation Air Dominance (NGAD) manned fighter.

Such NGAD advanced engine development—Next Generation Adaptive Propulsion (NGAP)—would receive $595 million in fiscal 2024, as opposed to $220 million appropriated by Congress last year, according to budget documents.

That $220 million appropriated for NGAP in fiscal 2023 was a nearly $153 million increase over the Air Force budget request (Defense Daily, Jan. 4).

Pratt & Whitney developed ECU, a block upgrade for the F135, with the objective of providing an affordable, low risk, and agile pathway to fielding meaningful propulsion capability for all F-35 customers. (Photo: Pratt & Whitney)

Five companies–General Electric, Pratt & Whitney, Boeing, Lockheed Martin, and Northrop Grumman–received contracts last year under an umbrella, $975 million effort for the prototype phase of…