Bell 47G-3B-1 N80SD

Summary

On 20 April 1998 at about 00:30 local time, a Bell 47G-3B-1 registered N80SD, operated by Helfenberger, Daniel, E., was involved in an accident near Sedro Wooley, Washington, United States. 3 people were on board and nobody was injured. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

20 April 1998 at 00:30

Classification

Accident

Location

Sedro Wooley, Washington, United States

Coordinates

48.5898, -122.1290

Aircraft

Bell 47G-3B-1

Registration

N80SD

Category

Helicopter

Engines

1

Operator

Helfenberger, Daniel, E.

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Unknown → Arlington

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

SEA98LA064

Nobody was injured.

Fuel contamination and subsequent carburetor fuel flow restriction initiated by the use of an improper material (incorrect fuel hose). A factor was the trees.

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

Read the full NTSB narrative

During initial climb immediately after takeoff the helicopter lost power. The pilot attempted to maneuver to a clear area, but struck trees during the descent. Post crash examination revealed no mechanical malfunction with either the engine or carburetor although the carburetor had been subjected to a post crash fire and its fuel metering orifices could not be bench tested. Fuel samples taken from the helicopter's fuel tank prior to the accident, and from the fueling hose from the portable fuel truck were examined by a fuels testing lab and were found to contain 1,2-Benzenedicarboxylic acid, bis(2-ethylhexyl) ester. The pre-accident aircraft fuel sample, which contained a submersed glob of clear substance similar to that observed by the pilot seeping from the cut ends of the fueling hose, was tested. The test revealed that the 'soluble gum' consisted of 1,2-Benzenedicarboxylic acid, bis(2-ethylhexyl) ester' and that nearly 100% of the gum was soluble in the fuel. The operator was advised by the local distributor of the 'Versicon' hose that the hose was acceptable for use with aviation fuels. Specifications provided by the manufacturer of the hose, HBD Industries, provided a note which stated 'Not recommended for the variety of unleaded gas existing presently.'

Quoted verbatim from the NTSB record.