-Maintain a variant common engine for the joint F-35 engine upgrade, by fully funding the F135 Engine Core Upgrade without delay, in order to maintain a cost affordable sustainment structure, avoid a bifurcated fleet, and to provide required cooling needs for critical block 4 upgrades by 2028.

Discussion/Program Status:
ECU fully enables the next block upgrade and has the fastest timeline of any propulsion modernization option (operational fielding in 2028). A core upgrade maintains critical sustainment infrastructure – avoiding the need to standup a duplicative and costly sustainment network, while retaining the substantial investments made by the Government and industry to date. ECU is also the only true “drop in” solution, allowing retrofits to the existing fleet during planned depot overhauls. This option will maintain a common global fleet by ensuring that all F-35s are able to be upgraded. Leveraging depot overhauls for retrofits will also significantly reduce costs and expedite the fielding schedule. Since the program’s inception, the F135 has reduced production costs by 50%. By leveraging the existing, well-established production line and maintaining 70% parts commonality, production costs for a core upgrade will remain neutral.
Funding in FY24 will ensure that Block 4 capabilities for the F-35 will be delivered in quantity and in time to maintain advantage over our adversaries. Fully funding the F135 ECU in FY24 is the only way to ensure timely delivery of critical capabilities to the warfighter.

FY24 RTX Recommended:
Fully fund the F135 Engine Core Upgrade (ECU) Engineering, Manufacturing and Development (EMD) in FY24 at $431.8M (RDT&E, Air Force, Line 143, F-35 C2D2, PE 0604840F; RDT&E, Navy, Line 197, F-35C C2D2, PE 0604840N; RDT&E, Navy, Line 196, F-35B C2D2, PE 0604840M) in order to maintain an Initial Service Release (ISR) date in 2028.