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December 11, 2012 · Piper PA-18-150 · N3471Z

Okaton, SD

Overview

Report Status
Final with probable cause
Event Type
Accident
Date
December 11, 2012
Injury Outcomes
No injuries (1 uninjured)
Location
Okaton, SD
Aircraft
Piper PA-18-150
Tail Number
N3471Z
Injuries
None
Aircraft Damage
Substantial
NTSB Number
CEN13CA108

The pilot reported that 2 days before the accident, snow accumulated on the airplane’s wings while it was parked in an open front hangar. The day before the accident, the temperature was warmer, and the pilot believed that the snow melted and ran rearward to the aileron gap/hinge locations, re-freezing during the nighttime hours. On the day of the accident, the pilot was in a hurry to use the airplane to check his pastures and brushed the snow off of the wings but did not perform a thorough preflight check of the airplane, including checking freedom of movement of the ailerons. After takeoff, the airplane began turning to the left. The pilot attempted to correct the turn, but the airplane did not respond. When he looked out at the wings, he could see that the ailerons were not responding to control inputs as they should. As he was attempting to regain control, the airplane descended into trees, resulting in substantial damage to both wings, the fuselage, and tail surfaces. A postaccident examination of the airplane revealed no mechanical defects that were determined to have existed before the accident.

NTSB Probable Cause

The pilot's failure to perform an adequate preflight inspection of the airplane and obstruction of the aileron control system by snow and ice, which led to a loss of control during flight.

Full Narrative

The pilot reported that two days prior to the accident, snow accumulated on the wings of the airplane while it was in an open front hangar. The day prior to the accident the temperature was warmer and the pilot believed that the snow melted and ran rearward to the aileron gap/hinge locations, re-freezing during the nighttime hours. The day of the accident the pilot said he was in a hurry to use the airplane to check his pastures and brushed the snow off of the wings, but did not perform a thorough preflight check of the airplane and did not check freedom of movement of the ailerons. After takeoff, the airplane began turning to the left. The pilot said that he attempted to correct, but there was no response. When he looked out at the wings, he could see that the ailerons were not responding to control inputs as they should. As he was attempting to regain control, the airplane descended into trees. A postaccident examination of the airplane revealed no defects that were determined to have existed prior to the accident. The airplane sustained substantial damage to both wings, the fuselage and tail surfaces.

Flight

Event TypeAccident
Event Time08:00 MST
Nearest AirportPrivate Airstrip (0nm)
Runway09
Flight Plan FiledNone
Flight Plan ActivatedNo
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftPiper PA-18-150
Tail NumberN3471Z
Aircraft CategoryAir
DamageSubstantial
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · O-320 SERIES · Reciprocating · 150
Seats2

People & Injuries

Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 54 · Third Class · None

Conditions

ConditionsVMC
LightDaylight
Wind320° @ 5 kt
Visibility10 sm
CeilingOvercast 9500 ft
Temperature / Dew Point19 C / 16 C
Altimeter29.85 inHg
Observation Time14:55
Weather SourceWFAC

Appendix: Source Data