Senate authorizers want to add $1.7 billion to the Air Force’s fiscal year 2022 budget request for F-35A retrofit modifications, calling on the service to move “expeditiously” to upgrade older jets to the Block 4 configuration. The proposed plus-up, included in the Senate Armed Services Committee’s version of the FY-22 defense authorization bill released Wednesday, would fund Technology Refresh 3 upgrades for 338 jets in low-rate initial production lots 1-13. The TR-3 modifications are foundational to enable most of the...