What happened
Prior to the flight, the pilots of a MiG 21 and a Piper PA-42 Cheyenne III coordinated a mission where the Cheyenne would perform aerial photography of the jet. The flight plan established a minimum altitude between 2,500 and 3,000 feet AGL and a minimum airspeed of 200 knots, though no specific separation distance was set. Following takeoff, the MiG 21 pilot encountered issues with the landing gear retraction. After a successful gear cycle, the Cheyenne pilot intended to rendezvous with the jet to visually inspect the landing gear mechanism.
During the maneuver, the MiG 21 was performing a 30-degree right-hand turn at 9,000 feet MSL and 200 knots with approach flaps deployed. The MiG 21 pilot observed the Cheyenne III approaching from the 5 o'clock position, approximately 300 to 400 feet behind and at a similar altitude. At this proximity, the Cheyenne III was positioned directly within the path of the high-velocity jet exhaust from the MiG 21. After a brief period of lost visual contact, the Cheyenne pilot attempted to communicate a comment regarding the landing gear or gear door but was unable to finish the transmission. Shortly thereafter, the MiG 21 pilot observed smoke rising from the desert floor and alerted air traffic control.
Findings
The wreckage of the Piper PA-42 Cheyenne III was found inverted on flat terrain, with the T-tail assembly separated and located roughly half a mile south of the primary debris field. Analysis of the aft vertical spar showed a bend and twist at the separation point, though no signs of fatigue, corrosion, or pre-existing cracks were found. Investigations of the MiG 21 revealed no evidence of physical contact with the other aircraft. The investigation noted that the Piper PA-42 Cheyenne III was positioned in the direct path of the high-velocity jet core exhaust during the encounter.