The Pentagon awarded $1.29 billion to Pratt & Whitney for a range of spare parts for F135 engines, the propulsion system powering F-35 Joint Strike Fighter jets. The “indefinite delivery, indefinite quantity” contract covers the spare parts required for engines upon initial delivery, spare parts packages for deployable aircraft, spares to be held in inventory at F135 service depots, and associated support equipment in support of U.S. and international F-35 operators.

Pratt & Whitney is the sole supplier of the F135, an afterburning turbofan engine for the Joint Strike Fighter series, which includes three aircraft models for different takeoff and landing requirements. It has manufactured and supplied over 1,500 F135s for the aircraft now in service with the U.S. and more than a dozen other allied nations.

Many of the service and sustainment requirements for F-35 engines are related to the Engine Core Upgrade (ECU) effort, to improve the propulsion system capabilities in anticipation of the F-35 Block 4 update. Block 4 is the label for U.S. Dept. of Defense’s broader plan to upgrade the F-35 aircraft to incorporate more sensor and weapons technologies and electronic warfare capabilities.

Pratt & Whitney reported the ECU “will leverage the established F135 sustainment network to provide global F-35 operators with proven, cost-effective sustainment.”

The contract is scheduled to run through December 2030. Nearly 80% of the work involved in fulfilling the contract will be performed at Pratt & Whitney locations in East Hartford and Middletown, Conn.

"Ensuring the F135 remains mission-ready is critical to the success of the F-35 enterprise," said Chris Johnson, vice president of Pratt & Whitney's F135 Program. "This contract will help strengthen our global sustainment network to ensure operators around the world can continue to rely on the F135's unmatched performance."

In March the Pentagon finalized terms with Pratt for the current production series, 148 engines scheduled for delivery in 2026-27.