Pilot Debrief

FINNEY THORP T-18 near Willcox, AZ — 2010-08-26

Final reportWPR10LA429
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Date
2010-08-26
Location
Willcox, AZ, USA
Airport
P33
Aircraft
FINNEY THORP T-18
Registration
N467JF
Category
Airplane
Highest injury
Fatal
Fatalities
2
Phase of flight
Approach

Probable cause

The pilot’s failure to maintain sufficient airspeed during a steep turn and at a low altitude in the traffic pattern, which resulted in an aerodynamic stall.

NTSB narrative

The airplane was observed in the traffic pattern, about 500 feet above ground level, when it made a steep left turn to enter the downwind leg. The turn continued as the airplane entered a left descending spiral until it impacted the ground in a nose-low attitude. Postaccident examination of the airframe and engine revealed no evidence of a mechanical malfunction or failure that would have precluded normal operation. The Pilot Operating Handbook for the airplane indicated that the airplane has an abrupt stall with a tendency to drop a wing, especially if the airplane is in an uncoordinated turn during the stall. There is very little warning preceding the stall. Stall recovery can be quickly affected by releasing back pressure on the stick; however, a secondary stall may occur if the stick is brought back abruptly after recovery without sufficient airspeed. It is likely that during the initial steep turn, the airplane entered an aerodynamic stall from which the pilot was unable to recover at the low altitude.

Analysis

Primary failure mode
Loss of control
First missed decision gate
Pilot could have avoided steep left turn entering downwind leg.

NTSB coding

Evidence available

  • Photos
  • 4 docket documents
View NTSB final reportView NTSB docket

Docket documents4

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