Accident Rans S-12-XL N933CW,
ASN logo
ASN Wikibase Occurrence # 287268
 
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information. If you feel this information is incomplete or incorrect, you can submit corrected information.

Date:Saturday 10 November 2012
Time:08:43 LT
Type:Silhouette image of generic RS12 model; specific model in this crash may look slightly different    
Rans S-12-XL
Owner/operator:Waller Charles R
Registration: N933CW
MSN: 03030963
Total airframe hrs:222 hours
Engine model:Rotax 912 ULS
Fatalities:Fatalities: 0 / Occupants: 2
Aircraft damage: Substantial
Category:Accident
Location:Gordon, Alabama -   United States of America
Phase: En route
Nature:Private
Departure airport:Gordon, AL
Destination airport:Ashford, AL
Investigating agency: NTSB
Confidence Rating: Accident investigation report completed and information captured
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.

Probable Cause: 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.

Accident investigation:
cover
  
Investigating agency: NTSB
Report number: ERA13LA052
Status: Investigation completed
Duration: 10 months
Download report: Final report

Sources:

NTSB ERA13LA052

Location

Revision history:

Date/timeContributorUpdates
04-Oct-2022 09:09 ASN Update Bot Added

Corrections or additions? ... Edit this accident description

The Aviation Safety Network is an exclusive service provided by:
Quick Links:

CONNECT WITH US: FSF on social media FSF Facebook FSF Twitter FSF Youtube FSF LinkedIn FSF Instagram

©2024 Flight Safety Foundation

1920 Ballenger Av, 4th Fl.
Alexandria, Virginia 22314
www.FlightSafety.org