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Pratt & Whitney mark a step in the evolution of the F-35’s propulsion system, with the preliminary design review (PDR) of the F135 Engine Core Upgrade (ECU). This development is set to improve the F-35’s operational capabilities.
The F-35 programme has had ongoing challenges, including late engine deliveries—over 90% from suppliers—and modernisation delays. The Department of Defense recently committed $497m for the F135 Engine Core Upgrade, now projected to cost $16.5bn and be complete by 2029. Pratt & Whitney invested $255m in a new facility in Oklahoma, the sole site capable of performing essential engine work.
The ECU is designed to enhance the F-35’s engine durability and performance to support the requirements of the Block 4 upgrade. This includes integrating next-generation weapons and sensors. The PDR saw Pratt & Whitney and the F-35 Joint Program Office evaluate the ECU’s design modifications and new propulsion technologies. These enhancements are intended to restore the engine’s full life span and improve overall performance.
The F-35 is a 5th-generation, single-seat, single-engine jet aircraft featuring advanced stealth technology suited for air superiority and strike missions. GlobalData’s US defence market intelligence highlights several F-35 variants designed to meet different operational needs.
Chris Johnson, vice president of Pratt & Whitney’s F135 program, emphasised the importance of this upgrade: “Upgrading the F-35’s propulsion system to ECU is a critical step toward ensuring the F-35 remains the world’s premier air dominance fighter.” This statement highlights the value of the ECU in maintaining the F-35’s competitive edge in modern air combat scenarios.
The US Department of Defense decided to select the F135 ECU as the sole modernisation solution earlier this year.
US Navy Capt. Mitchell Grant, F-35 propulsion program manager, lauded the successful PDR as a foundational milestone: “The PDR was a successful first step toward the capability the ECU will provide in meeting the challenging performance and durability requirements of the F135.” His remarks emphasise the importance of the ECU.
Since its inception, Pratt & Whitney has delivered more than 1,200 F135 production engines. The new ECU will be implemented in F-35s during production or retrofitted at various F135 depot sustainment facilities globally, ensuring that all F-35 variants worldwide will benefit from the upgrade.