Pratt & Whitney’s F135 engine for the F-35 Lightning II Joint Strike Fighter has amassed more than 6,000 hours of testing system development and demonstration ground testing, in addition to the more than 3,600 hours logged during the concept demonstration phase of the F-35, according to a company press release. P&W, which recently supervised a full after-burner test, says the engine is ready for F-35 taxi testing slated for later this fall.
2026 NDAA: 5 Highlights for Airmen and Guardians
Dec. 18, 2025
President Donald Trump signed the 2026 National Defense Authorization Act on Dec. 18, a day after Congress passed the annual defense policy bill for the 65th consecutive year. Here’s what it means for the Air Force and Space Force.

