Central Ohio Dragonfly Club DRAGONFLY-C N667DF

Summary

On 4 November 2012 at about 17:30 local time, a Central Ohio Dragonfly Club DRAGONFLY-C registered N667DF, operated by Central Ohio Dragonfly Club, LLC, was involved in an accident near Darbyville, Ohio, United States. One person was on board and one was seriously injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

4 November 2012 at 17:30

Classification

Accident

Location

Darbyville, Ohio, United States

Nearest airport

WesMar Aerodrome (PVT)

Coordinates

39.7025, -83.1472

Aircraft

Central Ohio Dragonfly Club DRAGONFLY-C

Registration

N667DF

Category

Airplane

Year built

2006

Engines

1

Operator

Central Ohio Dragonfly Club, LLC

Operating rule

Part 91: General Aviation

Purpose of flight

Glider Tow

Phase of flight

Not recorded

Route

Darbyville → Darbyville

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CEN13LA055

1 person was seriously injured.

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.

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

Read the full 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.

Quoted verbatim from the NTSB record.