Features Becomes Upgrades

Some capabilities planned for the F-35 Block 3F—the planned all-up configuration for all three services flying variants of the fighter—will migrate to the Block 4 upgrade, Air Force F-35 integration director Maj. Gen. Jeff Harrigian explained Thursday. Most of the planned 3F capabilities that will become part of the first upgrade package live “in the classified world,” Harrigian said, begging off detailing what they are. “Some of it is hardware-driven, some of it’s software driven,” he told reporters after an AFA Mitchell Institute event. However, he said USAF is working to find “mitigation strategies” to make sure some of those capabilities “don’t move” from the 3F configuration. USAF is trying to determine, “What’s the constraint? Is it time? Is it money? … And, that’s the discussion we need to have” with the Joint Program Office, he said.