20230817008199A

While conducting a part 141 checkout training flight in a training area 10 miles southwest of the airport, the aircraft broke apart losing both its wings and the horizontal stabilizer before crashing nose down into a storage structure on private property. The wings and stabilizer were found in a field less than 1/10TH of a mile east, with a larger debris field to the north east, consisting of mostly cabin interior items and half of the entry door. Upon initial investigation, it was evident that the wings had signatures indicating upward pressure towards the fuselage, the attach points having sheared due to the excessive load. The fuselage was inspected after it was pulled from the storage facility by the recovery company. The center wing box exhibited evidence of failing in compression, with the upper, center portion having clear failure point, waves in the metal at the end roots, and nearly all rivets sheared off the upper cap. The NTSB cut and took possession of the center box for metallurgical testing. Flight data shows that the aircraft has descended from 4700 ft to 1600 ft, and back to 3000 ft within a span of 20 seconds right before the crash.