Waller Charles R RANS S12-XL N933CW

Summary

On 10 November 2012 at about 14:43 local time, a Waller Charles R RANS S12-XL registered N933CW, operated by Waller Charles R, was involved in an accident near Gordon, Alabama, United States. 2 people were on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

10 November 2012 at 14:43

Classification

Accident

Location

Gordon, Alabama, United States

Coordinates

31.1333, -86.9000

Aircraft

Waller Charles R RANS S12-XL

Registration

N933CW

Category

Airplane

Engines

1

Operator

Waller Charles R

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Gordon → Ashford

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

ERA13LA052

Nobody was injured.

A fatigue failure of the elevator pitch trim cable, which resulted in aerodynamic flutter of the elevator in flight and the airplane’s subsequent nose-over during the resultant precautionary landing.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

As the pilot leveled the airplane after departure and accelerated to cruise airspeed, the airplane's elevator suddenly began to flutter violently, shaking the airplane. The pilot reduced airspeed in an attempt to stop the elevator from fluttering, but the elevator continued to flutter. As a result of the flutter, the control column was moving rapidly forward and aft about 6 inches, which would correspond to an elevator up and down movement of about 20 degrees. The pilot decided to make an emergency landing in a cow pasture because he was worried about a structural failure. Upon touchdown on the cow pasture, the nosewheel dropped into a hole, and the airplane nosed over and came to rest inverted. Postaccident examination revealed that the fuselage was substantially damaged, and the trim push wire that actuated the elevator trim tab was fractured. Examination of the trim push wire revealed that it had been secured to the trim tab by a wire swivel/screw stop that was attached to the trim horn. Further examination revealed that the trim push wire was bent and had fractured just forward of the wire swivel/screw stop. The fracture face displayed corrosion and striations consistent with fatigue. Examination of the trim horn on which the wire swivel/screw stop was mounted also revealed wear, scratching, and gouging. The observed damage was consistent with the wire swivel/screw stop binding during operation and being unable to rotate under load. Airplane manufacturer personnel indicated that they observed a similar failure when spectators at an airshow leaned against a trim tab on an airplane that was on display, bending the trim push wire, which subsequently failed in flight.

Quoted verbatim from the NTSB record.