Pratt & Whitney has received full funding in the recently passed fiscal year 2024 Defence Appropriations bill for its F135 engine core upgrade (ECU). This will modernise the F-35’s propulsion system to ‘increase durability and fully-enable Block 4 capabilities and beyond’ starting in 2029.

Jill Albertelli, president of Pratt & Whitney Military Engines, said: “This bill will allow Pratt & Whitney to deliver the current and future propulsion capabilities that will keep the United States and its allies on the cutting edge of fighter engine technology.”

Some $497 million was allocated to the F135 ECU, which will move into detailed design later this year. The ECU is compatible with all three variants of the F-35, will be retrofittable, and will be available to all F-35 operators. The ECU will use the same F135 global sustainment network and domestic workforce already in place, supporting more than 57,000 jobs and 225 suppliers that contributed more than $2.2 billion to the US economy in 2023.

The defence bill also includes continued support for the Next-Generation Adaptive Propulsion programme, a portion of which will be provided for Pratt & Whitney’s XA103 adaptive engine to continue moving toward detailed design review for the prototype engine. Pratt & Whitney says it ‘remains well-positioned to support concurrent development programmes with the capacity and expertise to meet customers’ evolving propulsion needs’.