All three F-35 variants underwent cold-weather testing at Eielson AFB

All three variants of the F-35 were brought to Eielson Air Force Base, Alaska for cold weather testing by the Joint Strike Fighter Operational Test Team (JOTT).

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U.S. Air Force photo by Airman 1st Class Isaac Johnson

This was part of the pre-Initial Operational Testing and Evaluation test event for the fighter.