This accident occurred on an aerobatic training mission. While entering a loop the aircraft experienced a structural failure of the wing. The left wing folded up over the fuselage causing the aircraft to enter an extreme roll. The instructor was Capt. Swanson, who ejected from the back seat at what the USAF estimated to be 550 kts. Swanson was killed due to the extreme forces caused by the high speed ejection. The student (can’t remember his name) ejected at a slower speed (under 500 kts) and was seriously injured. He was eventually medically retired from the USAF, having never regained flight status.

 During the accident investigation it was shown that the accident aircraft had a fatigue crack in the wing that had been missed on previous inspections. The crack propagated from the cutout in the spar for the main gear tire and spread across the narrow part of the spar over a long period of time. It was determined that this crack started at a stress riser caused by the manufacture’s machining practices when the wing planform was built in 1966.

Subsequently the entire T-38 fleet was grounded worldwide while every aircraft was inspected in the wheel well area by eddy current looking for cracks. As I recall at Sheppard they found two aircraft that were grounded for a long period of time awaiting parts. I have no idea how many aircraft were found with cracks worldwide, but there was a large backlog of orders for the T-38 wing that took a long time to fill. The rest of the fleet was back in the air in about ten days as the inspections and polishing of the suspect areas were completed.

I hope this fills in one of the many blanks in your data

Steve Clarke

T-38 Instructor Pilot a long time ago
in email 5th February 2008