Enstrom 280 N36DK accident near Colchester, Vermont

Jul 30, 2021 · NTSB number ERA21LA309 · Final report

Probable cause

An in-flight fire originating in the engine compartment near the turbocharger from a source that could not be determined, which resulted in a loss of engine power and led to an autorotation and a hard landing.

NTSB analysis

The commercial pilot reported that while enroute he smelled and then observed smoke in the cockpit. He also observed a rapidly rising exhaust gas temperature despite moving the mixture to full rich. The pilot initiated a precautionary landing during which the helicopter experienced a partial and then total loss of engine power. During the final segment of the autorotation, the helicopter impacted trees and landed hard on a causeway.

Postaccident examination of the engine found significant soot and thermal damage, which precluded a determination of the specific source of the in-flight engine fire. However, one cause of the fire could be eliminated. Specifically, the heaviest area of thermal damage was located around the No. 3 cylinder near the turbocharger. The outer portion of the turbocharger displayed significant thermal damage, but the turbocharger exhaust and inlet clamps were intact and remained tightly installed with safety wires present. Therefore, leakage of exhaust gases from the turbocharger was not the cause of the in-flight fire.

The external damage to the turbocharger indicated that its high temperature surfaces were possible ignition sources for an ignitable liquid, such as lubricating oil or fuel. The flexible fuel and oil lines all displayed significant thermal damage, and some were destroyed by fire. Several oil lines were located near the thermal damage in the forward left portion of the engine compartment. Therefore, lubricating oil from these lines was a possible fuel source for the fire. In addition, because the flexible fuel lines were either damaged or destroyed, fuel from these lines could not be eliminated as a source of fuel for the in-flight fire.

Text from the NTSB. Open the NTSB docket for ERA21LA309 for the full record.

Event

Date
Jul 30, 2021
Type
Accident
Place
Colchester, Vermont
Highest injury
Serious
Serious injuries
1
Weather
Visual (VMC)
Light
Day

Enstrom 280

N-number
N36DK
Category
Helicopter
Year built
1985
Damage
Destroyed
Operating rule
Part 91 (general aviation)
Purpose of flight
Personal

From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.