Pilot Debrief

CENTRAL OHIO DRAGONFLY CLUB DRAGONFLY-C near Darbyville, OH — 2012-11-04

Final reportCEN13LA055
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Date
2012-11-04
Location
Darbyville, OH, USA
Airport
PVT
Aircraft
CENTRAL OHIO DRAGONFLY CLUB DRAGONFLY-C
Registration
N667DF
Category
Airplane
Highest injury
Serious
Fatalities
0
Phase of flight
Initial climb

Probable cause

The total loss of engine power due to a cold-seizure event that occurred at a low altitude, which precluded the pilot's recovery from an inadvertent aerodynamic stall/spin.

NTSB narrative

The accident occurred during an aero-tow of a hang glider. The pilot reported that during initial climb, about 80 feet above the runway, the airplane experienced a sudden and total loss of engine power while it was in a climbing left turn. He stated that the airplane immediately entered an aerodynamic stall/spin following the loss of engine power. The pilot released the towed hang glider, but he was unable recover from the aerodynamic stall condition before the airplane impacted terrain. A postaccident examination of the two-cylinder engine revealed excessive piston scoring within one of the cylinder assemblies and excessive wear on the piston wrist-pin. The observed anomalies were consistent with a cold-seizure event. A cold-seizure event is a thermo-imbalance condition between the piston and cylinder, which results in an insufficient clearance between the piston and the cylinder. The cylinder thermo-imbalance condition is typically the result of an insufficient engine warm-up period before takeoff power is applied. However, the conditions that led to the cold-seizure event may not have been limited to the accident flight. The total loss of engine power during initial climb, while towing a hang glider, likely contributed to the aerodynamic stall/spin encountered at a low altitude. Additionally, the low altitude at which the aerodynamic stall/spin was encountered was likely insufficient to have allowed a recovery before the airplane impacted terrain.

Analysis

Primary failure mode
Engine power loss
First missed decision gate
Insufficient engine warm-up before takeoff power was applied.

NTSB coding

Evidence available

  • 2 docket documents
View NTSB final reportView NTSB docket

Docket documents2

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