Pratt & Whitney has completed the F135 Engine Core Upgrade risk reduction design review in East Hartford, Connecticut, clearing another development step for the F-35 engine modernisation effort. The review covered detailed design elements, propulsion technologies and integration work for the upgrade, which is intended to add power and thermal-management capacity for Block 4 and later capabilities across all three F-35 Lightning II variants.
The ECU is being developed as a drop-in replacement for both new-build and fielded aircraft, giving the programme a retrofit path as well as a route into future production. Pratt & Whitney said the review validated the maturity of the design and moved the effort closer to production.
The work is supported by a contract awarded in 2024 and includes design maturation, aircraft integration, test preparation, supply-base readiness and related engineering activities. U.S. Navy Capt. Mitch Grant, the F-35 Propulsion Program Manager, described the review as evidence of strong collaboration between government and industry teams and of a mature ECU design.
Jill Albertelli, president of Pratt & Whitney Military Engines, called the review completion a major milestone in the effort to deliver the capability to warfighters.