Program remains on track to fully enable the F-35's future needs EAST HARTFORD, Conn., July 15, 2024 /PRNewswire/ -- Pratt & Whitney, an RTX (NYSE: RTX) business, completed the F135 Engine Core Upgrade's (ECU) preliminary design review (PDR), affirming the ECU's design is on schedule and exceeding expectations. The upgrade will deliver increased engine durability and performance that will fully enable Block 4 and beyond capabilities for all three variants of the F-35 worldwide.During the PDR, Pratt & Whitne ...