Hydraulic fluid contaminated with water froze inside the landing gear of an F-35A Lightning II, causing the jet to crash during a training flight at Eielson Air Force Base, according to an Accident Investigation Board (AIB) report released on Tuesday by Pacific Air Forces.
The aircraft, assigned to the 355th Fighter Squadron of the 354th Fighter Wing, exploded and was destroyed in the Jan. 28 incident. The pilot declared an in-flight emergency before the crash and ejected safely.
Longer Footage of the F-35A Crash earlier today at Eielson Air Force Base in Alaska. pic.twitter.com/9OPksbTYWj
— OSINTdefender (@sentdefender) January 29, 2025
Investigators found that ice formed in hydraulic fluid contaminated with water inside the nose and main landing gear struts, preventing them from fully extending. This caused the “weight on wheels” sensors to incorrectly indicate that the jet was on the ground. As a result, the aircraft automatically switched into ground mode. “However, because it was actually airborne, the [mishap aircraft] was uncontrollable,” the report stated.
Investigators also noted that another F-35 experienced a similar hydraulic freezing malfunction just nine days before the incident.
According to the AIB, the pilot spent 50 minutes on a conference call with the Eielson supervisor of flying, engineers, and Lockheed Martin, the aircraft’s manufacturer, before losing control of the plane.
The report also cited crew decision-making, lapses in following maintenance procedures for hydraulic safety equipment, and inadequate oversight of the fighter generation squadron’s hazardous materials program as contributing factors in the crash.
The report did not recommend any changes to current policies or procedures. Authorities valued the destroyed aircraft at $196.5 million.
