# NTSB CHI90DER03: Bell 47G3B1, N4990H, Coon Rapids, MN, July 31, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: July 31, 1990, 10:07 local (15:07 UTC)
- Place: Coon Rapids, MN
- Coordinates: 45.159713, -93.310752 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.1597&lon=-93.3108&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report September 21, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 14487
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI90DER03
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14487/pdf
- Page: https://openairdocs.org/ntsb/CHI90DER03

## Probable cause

THE PILOT-IN-COMMAND'S INACCURATE FUEL CONSUMPTION CALCULATIONS AND MISJUDGEMENT OF HIS FUEL SUPPLY.

## Sequence of events

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

- Loss of engine power(total) - nonmechanical, cruise - normal
  - fuel system,tank - exhaustion (contributing factor)
  - fuel supply - misjudged, pilot in command (cause)
  - fuel consumption calculations - inaccurate, pilot in command (cause)
- Forced landing, descent - emergency
  - emergency procedure - initiated, pilot in command (contributing factor)
  - autorotation - attempted, pilot in command (contributing factor)
- Hard landing, landing - flare/touchdown
  - flare - misjudged, pilot in command (cause)

## Analysis

WHILE IN NORMAL CRUISE FLIGHT, THE HELICOPTER EXPERIENCED A TOTAL LOSS OF ENGINE POWER. AN AUTOROTATIONAL LANDING WAS ATTEMPTED, HOWEVER THE PILOT MISJUDGED THE FLARE AND LANDED HARD RENDERING SUBSTANTIAL DAMAGE TO THE AIRCRAFT. SUBSEQUENT INVESTIGATION REVEALED ONLY UNUSABLE FUEL IN THE TANKS OF THE HELICOPTER. WHEN FUEL WAS ADDED TO THE TANKS THE ENGINE RAN NORMALLY.

## Aircraft

- Registration: [N4990H](https://openairdocs.org/aircraft/N4990H), registered now, S/N 2942, built 1964 (OpenAirDocs)
- Reported make and model: BELL 47G3B1
- Registry model: [Bell 47G-3B-1](https://openairdocs.org/model/bell-47g-3b-1) (registry code 1181028) (OpenAirDocs)
- Registry engine: [Lycoming TVO-435-GIA](https://openairdocs.org/engine/lycoming-tvo-435-gia) (registry code 41526, turbo-prop) (OpenAirDocs)
- Category: Helicopter
- Serial number: 2942
- Airframe hours: 4410
- Engines: LYCOMING VO435A1F 260 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Registered owner: Scott Churchill
- Airworthiness certificate: Special, Restricted (Special); Standard, Normal
- Last inspection: 100 hour, June 13, 1990, 40 hours before
- Departed: COON RAPIDS, MN
- Destination: ANE, ANOKA CO., MN

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 37; private, commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: left; flight hours: 8,000 total, 7,000 in this make and model, 7,550 as pilot in command, 15 in the last 90 days, 50 in the last 30 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 240° at 8 knots
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 70 °F, dew point 54 °F
- Altimeter: 30.00 inHg
- Observed at: MSP, 16 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 19900731029399A](https://openairdocs.org/incident/19900731029399A), Jul 31, 1990: Bell 47G3B1, Coon Rapids, MN, Substantial damage. On return to base after a spray operation engine quit. Autoratated to tail strike landing. Was out of fuel.

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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