Incident Overview
A pilot reported that while cruising at an en route altitude of 4,500 ft MSL, he encountered no turbulence. He initiated a descent by reducing power to 20 inches of manifold pressure and applying light forward pressure on the yoke. During the descent, the pilot felt a violent shudder and immediately released the pressure on the yoke, which caused the shudder to cease.
Post-Flight Inspection
Following the flight, inspection of the airplane revealed buckled and wrinkled skin, popped rivets, and bulkhead cracks. Examination of the rudderovators disclosed improper hardware installation, a loose bearing, and improperly installed elevator trim tabs.
Rudderovator Balance Testing
The rudderovators were tested for balance. The right rudderovator had a balance of 19.26 inch-pounds, which fell within the balance limits of 16.8 to 19.8 inch-pounds. The left rudderovator had a balance of 20.05 inch-pounds, which was outside the specified balance limits.
The source did not provide further details regarding the aircraft type, registration, operator, date, location, occupants, or injuries.