Aerospatiale AS350 N369BD

Summary

On 28 October 2016 at about 19:40 local time, a Aerospatiale AS350 registered N369BD, operated by Leading Edge Aviation LLC, was involved in an accident near Starbuck, Washington, United States. One person was on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

28 October 2016 at 19:40

Classification

Accident

Location

Starbuck, Washington, United States

Nearest airport

Little Goose Lock and Dam (16W)

Coordinates

46.5883, -118.1231

Aircraft

Aerospatiale AS350

Registration

N369BD

Category

Helicopter

Year built

1983

Operator

Leading Edge Aviation LLC

Operating rule

Part 137: Agricultural

Purpose of flight

Aerial Application

Phase of flight

Not recorded

Route

Starbuck → Starbuck

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

WPR17LA014

Nobody was injured.

A total loss of engine power due to fuel exhaustion, which resulted from the pilot’s reliance on the fuel gauge that was displaying an incorrect fuel amount due to the separation of the fuel transmitter float pin guide from the float.

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

Read the full NTSB narrative

The commercial pilot reported that, during the agricultural application flight in the helicopter, the fuel pressure warning light illuminated. The pilot scanned the instruments and noted that the fuel pressure was low and that the fuel quantity was indicating between 40% and 50%. Subsequently, the engine started to lose power. The pilot entered an autorotation and set up the helicopter for landing in the flattest area. Subsequently, the helicopter landed hard, which resulted in substantial damage to the tailboom and main rotor assembly. Postaccident examination of the helicopter revealed that the fuel tank was intact, undamaged, and empty of fuel. Given this evidence, the engine likely lost all power due to fuel exhaustion. Despite the lack of fuel, the fuel quantity gauge indicated that 42% of the fuel was remaining (or about 60 gallons). Disassembly of the fuel transmitter revealed that the float guide pin was separated from the float assembly at the tack weld. The separation of the float guide pin allowed the float to slide down the center torque shaft and prevented the potentiometer drive plate at the bottom from rotating when the fuel quantity changed, which led to the fuel quantity gauge displaying an incorrect fuel level. A review of the airplane's maintenance records revealed that the fuel transmitter was overhauled about 11 months before the accident. Given the evidence, it is likely that, during the overhaul, maintenance personnel improperly welded the float pin guide to its mount and subsequently did not adequately inspect it, which led to its eventual separation from the assembly at the welded area.

Quoted verbatim from the NTSB record.