What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) Pilot john cosman ii and wife jane were transitioning into the ykm airport at 5000 MSL with clearance to land while crossing the last ridge when the aircraft started to shake/flutter violently. Pilot john cosman reduced power and pulled the nose up. The shaking/vibration stopped. Review of aircraft revealed a one time structural overload of the rear empennage structure just ahead of the 256 bulkhead. The fuselage bent tortionally down and to the right sufficiently to bend fuselage longerons, tear skin away from rivets, and crack side skin. No bulkhead was damaged. The ruddervators were checked for balance and were well within balance specifications. It was not possible to verify cable tensions. The records indicate a well maintained aircraft with no issues in relation to this accident. (Other) this aircraft met type design at the time of the incident. Ntap reports show it was being flown within the scope of its normal flight envelope. Other aircraft of this design have also experienced one time turbulence damage like this aircraft. A safety recommendation will be written on this aircraft series.
As the FAA filed it
(-23) PILOT JOHN COSMAN II AND WIFE JANE WERE TRANSITIONING INTO THE YKM AIRPORT AT 5000 MSL WITH CLEARANCE TO LAND WHILE CROSSING THE LAST RIDGE WHEN THE AIRCRAFT STARTED TO SHAKE/FLUTTER VIOLENTLY. PILOT JOHN COSMAN REDUCED POWER AND PULLED THE NOSE UP. THE SHAKING/VIBRATION STOPPED. REVIEW OF AIRCRAFT REVEALED A ONE TIME STRUCTURAL OVERLOAD OF THE REAR EMPENNAGE STRUCTURE JUST AHEAD OF THE 256 BULKHEAD. THE FUSELAGE BENT TORTIONALLY DOWN AND TO THE RIGHT SUFFICIENTLY TO BEND FUSELAGE LONGERONS, TEAR SKIN AWAY FROM RIVETS, AND CRACK SIDE SKIN. NO BULKHEAD WAS DAMAGED. THE RUDDERVATORS WERE CHECKED FOR BALANCE AND WERE WELL WITHIN BALANCE SPECIFICATIONS. IT WAS NOT POSSIBLE TO VERIFY CABLE TENSIONS. THE RECORDS INDICATE A WELL MAINTAINED AIRCRAFT WITH NO ISSUES IN RELATION TO THIS ACCIDENT. (OTHER) THIS AIRCRAFT MET TYPE DESIGN AT THE TIME OF THE INCIDENT. NTAP REPORTS SHOW IT WAS BEING FLOWN WITHIN THE SCOPE OF ITS NORMAL FLIGHT ENVELOPE. OTHER AIRCRAFT OF THIS DESIGN HAVE ALSO EXPERIENCED ONE TIME TURBULENCE DAMAGE LIKE THIS AIRCRAFT. A SAFETY RECOMMENDATION WILL BE WRITTEN ON THIS AIRCRAFT SERIES.
Other reports on N4647D · 3
Matched to the same aircraft by N-number and date.