Enstrom 280 N280MM

Summary

On 24 June 2020 at about 00:01 local time, a Enstrom 280 registered N280MM was involved in an accident near Hayden, Idaho, United States. 2 people were on board and one died, one was seriously injured. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

24 June 2020 at 00:01

Classification

Accident

Location

Hayden, Idaho, United States

Coordinates

47.7750, -116.8956

Aircraft

Enstrom 280

Registration

N280MM

Category

Helicopter

Year built

2003

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Instructional

Phase of flight

Not recorded

Route

Coeur D' Alene → Coeur D' Alene

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

WPR20LA191

1 person died.

The total loss of power while maneuvering at low altitude due to the detonation of two engine cylinders and damaged spark plugs. 

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

Read the full NTSB narrative

Shortly after takeoff on an instructional flight, a helicopter was maneuvering at a low altitude when the engine rpm “skyrocketed,” and the engine lost total power; the flight instructor (who was at the controls) reported hearing “backfiring” at the time, although the engine was still running. The flight instructor then had to maneuver the helicopter to avoid nearby power lines, but the helicopter impacted terrain. The main rotor blades struck the tailboom, and the helicopter subsequently spun around about 180° before coming to rest. A postcrash fire then ensued, which consumed most of the helicopter. Additionally, the student pilot stated to a witness after the accident that the helicopter was losing power. An engine examination revealed that detonation had occurred in two of the four engine cylinders. (Detonation in a piston engine occurs when the fuel-air mixture in a cylinder detonates or explodes prematurely instead of being ignited by spark plugs and burning evenly and smoothly, as occurs with normal combustion.) Furthermore, damaged spark plugs were observed in one of the detonated cylinders as well as another cylinder. The combined effects of the detonation and damaged spark plugs likely caused the loss of engine power. Because the loss of power occurred at a low altitude, the flight instructor likely did not have enough altitude to adequately establish a steady-state autorotation to avoid the helicopter’s impact with terrain.

Quoted verbatim from the NTSB record.