# NTSB CHI90DEC04: Bell 47 D-1, N3656F, Stockbridge, MI, August 14, 1990

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Final report
- Date: August 14, 1990, 05:54 local (09:54 UTC)
- Place: Stockbridge, MI
- Coordinates: 42.449035, -84.170783 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.4490&lon=-84.1708&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report December 8, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 14445
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI90DEC04
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14445/pdf
- Page: https://openairdocs.org/ntsb/CHI90DEC04

## Probable cause

THE RESTRICTED VISUAL LOOKOUT WHICH RESULTED FROM THE CANOPY FOGGING UP.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- In flight collision with object, takeoff - initial climb
  - window,canopy - dirty(foggy) (cause)
  - visual lookout - restricted, pilot in command (cause)
  - object - pole
  - object - wire,static
- Fire, maneuvering
  - fuel system,tank - ruptured
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE AGRICULTURAL HEILCOPTER HAD JUST TAKEN OFF ON AN EARLY MORNING RE-POSITIONING FLIGHT WHEN THE CANOPY BECAME COMPLETELY FOGGED OVER. BEFORE THE PILOT COULD RE-ORIENT HIMSELF BY LOOKING OUT THE SIDE OPENING, THE HELICOPTER COLLIDED WITH A POWER POLE AND WIRES. THE COLLISION CAUSED THE FUEL TANK TO RUPTURE AND SPRAYED AVIATION FUEL ONTO THE HOT ENGINE AND EXHAUST PIPES. THE ENSUING FIRE DESTROYED THE HELICOPTER.

## Aircraft

- Registration: [N3656F](https://openairdocs.org/deregistered/N3656F-2002-02-12), registration cancelled 2002-02-12, S/N 307, built 1959 (OpenAirDocs)
- Reported make and model: BELL 47 D-1
- Registry model: [Bell 47D1](https://openairdocs.org/model/bell-47d1) (registry code 1180802) (OpenAirDocs)
- Registry engine: [Franklin 6V4 series](https://openairdocs.org/engine/franklin-6v4-series) (registry code 27033, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: 307
- Airframe hours: 5166
- Engines: FRANKLIN 6V4200-C32 200 horsepower reciprocating
- Damage: Destroyed
- Fire: In-Flight
- Flight: Ferry, Part 91
- Operator: Allied Helicopter Service, Inc
- Registered owner: Allied Helicopter Ser., Inc
- Airworthiness certificate: Special, Restricted (Special); Standard, Normal
- Last inspection: 100 hour, July 25, 1990, 62 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 54; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 13,149 total, 10,700 in this make and model, 10,309 as pilot in command, 240 in the last 90 days, 80 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Instrument (IMC), Dawn
- Wind: calm
- Visibility: 1 statute miles
- Lowest ceiling: none
- Temperature: 50 °F, dew point 50 °F
- Altimeter: 29.00 inHg
- Observed at: JXN, 17 nm away

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19900814032999A](https://openairdocs.org/incident/19900814032999A), Aug 14, 1990: Bell 47D1, Stockbridge, MI, Substantial damage. Windshield fogged on night flight at low altitude with high humidity. Struck pole and wires crashed and burned.

## Other investigations on N3656F (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB CHI80FEC26](https://openairdocs.org/ntsb/CHI80FEC26), Jul 30, 1980: Bell 47D1 (N3656F), Munith, MI, substantial damage, 1 fatal

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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