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.
842,000+ 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.
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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.
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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.
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Retrofit Ready
Retrofits allow for upgrades to already fielded F-35s and new production F-35s, ensuring a common capable fleet for all users.