F135 Engine Core Upgrade (ECU)
The F135 is the world’s most advanced fighter engine with proven readiness and reliability. The ECU builds upon that same architecture with a fleet-wide upgrade.
Combat proven. Variant common. Cost effective.
The future of the F-35 fighter jet.
Pratt & Whitney’s F135 Engine Core Upgrade (ECU) delivers the durability and performance needed to enable Block 4 capabilities and beyond. Easily retrofittable in all F-35 variants, ECU is the only engine that offers all global F-35 operators the additional power and thermal management capacity needed to enable next-generation weapons systems and sensors. Utilizing cutting-edge technologies developed for advanced programs, ECU ensures the F-35 Lightning II remains the most advanced fighter for decades to come.
Proven track record.
810,000+ Recorded Flight Hours
The ECU builds on the architecture of the F135—a proven engine with nearly 20 years of reliable performance. It is the only true drop-in, low-risk and cost-effective engine upgrade for the F-35.
57,000+ U.S. Jobs
The F135 program sustains more than 57,000 domestic jobs, 255 U.S. suppliers, and contributed more than $2.2 billion to the U.S. economy in 2023. Selection of the F135 ECU as the sole-source propulsion provider for the F-35 protects existing U.S. infrastructure investments and creates new skilled labor and engineering jobs year-over-year to support program growth.
Variant Common
Commonality is a pillar of the F-35 program. The ECU is the only engine upgrade that supports all three variants of the F-35, enabling joint maintenance efficiencies and leveraging existing infrastructure.
Fiscally Responsible
The ECU will cost approximately $2 billion to fully upgrade the engine—ultimately saving taxpayers 10s of billions over the F-35 program’s lifetime if chosen over alternative options.
Proven Technology
The ECU’s targeted changes utilize proven technology from the Navy’s Fuel Burn Reduction program and other advanced development programs.
Retrofit Ready
Retrofits allow for upgrades to already fielded F-35s and new production F-35s, ensuring a common capable fleet for all users.