# NTSB LAX84LA117: Bell 206B III, N206JH, Mountain City, NV, December 27, 1983

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: December 27, 1983, 12:00 local (16:00 UTC)
- Place: Mountain City, NV
- Coordinates: 41.77053, -116.07946 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=41.7705&lon=-116.0795&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 2 serious, 1 minor
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 24128
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX84LA117
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/24128/pdf
- Page: https://openairdocs.org/ntsb/LAX84LA117

## Sequence of events

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

- Loss of engine power(total) - mech failure/malf, maneuvering
  - fuel system,pump - improper (cause)
  - maintenance,replacement - improper, other maintenance personnel (cause)
- Forced landing, landing - flare/touchdown
  - weather condition - snow (contributing factor)
  - terrain condition - snow covered (contributing factor)

## Analysis

THE HELICOPTER COLLIDED WITH THE SNOW COVERED GROUND AFTER THE ENG QUIT DURING A POWER-LINE PATROL AT ABOUT 30 FT AGL. THE PLT REPORTED THAT THE VISIBILITY WAS 1/2 MILE WITH LIGHT SNOW FALLING. HE ALSO SAID HE COULD SEE 4 TO 7 OF THE SUPPORTING STRUCTURES. THESE POLES ARE SPACED ABOUT 350 FT APART SO SEVEN POLES TOTALS LESS THAN 1/2 MILE. THE BELL 206BFLT MANUAL STATES THAT 'OPERATIONS ARE PERMITTED IN FALLING SNOW WHEN VISIBILITY IS IN EXCESS OF 1/2 MILE, BUT FLT DURATION IS LIMITED TO 1 AND 1/2 HOURS.' INVESTIGATION OF THE ENGINE AFTER THE ACCIDENT REVEALED THAT WHEN THE TOP PLUG OF THE FUEL PUMP FILTER WAS LOOSENED, THE SOUND OF ESCAPING AIR WAS NOTED. INVESTIGATION ALSO REVEALED THAT ON THE DAY OF THE ACCIDENT THE FORWARD FUEL BOOST PUMP HAD BEEN REPLACED WITH A NEW IC-38-L TYPE PUMP WHICH HAD BEEN SIGNED OFF AS HAVING BEEN CHECKED FOR PRESSURE AND BLED.

## Aircraft

- Registration: [N206JH](https://openairdocs.org/deregistered/N206JH-2019-11-29), registration cancelled 2019-11-29, S/N 2918, built 1980 (OpenAirDocs)
- Reported make and model: BELL 206B III
- Registry model: [Bell 206B](https://openairdocs.org/model/bell-206b) (registry code 1181511) (OpenAirDocs)
- Registry engine: [Rolls-Royce 250-C20B](https://openairdocs.org/engine/rolls-royce-250-c20b) (registry code 54385, turbo-shaft) (OpenAirDocs)
- Category: Helicopter
- Serial number: 2918
- Airframe hours: 1220
- Engines: ALLISON 250-C20B 317 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Aerial observation, Part 91
- Operator: Idaho Helicopters
- Registered owner: Farm Development Corporation
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, November 4, 1983, 39 hours before
- Departed: BOISE, ID
- Destination: MOUNTAIN CITY, NV
- Flight plan: Company VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 52; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: helicopter, airplane; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 12,860 total, 3,500 in this make and model

## Weather

- Conditions: Instrument (IMC), Day
- Wind: 270° at 5 knots, gusting 5
- Visibility: 5 statute miles
- Lowest ceiling: 7,000 ft overcast
- Temperature: 18 °F

## 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 19831227064299A](https://openairdocs.org/incident/19831227064299A), Dec 27, 1983: Bell 206B3, Mountain City, NV, Substantial damage. Engine flameout on powerline patrol. Vertical impact in snow. Fuel pump contained air. No winter snow baffles.

## Other investigations on N206JH (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 WPR19LA122](https://openairdocs.org/ntsb/WPR19LA122), Apr 26, 2019: Bell 206 (N206JH), Oakridge, OR, substantial damage. Probable cause: A total loss of engine power following the failure of a 3rd stage turbine blade due to low- and high-cycle fatigue.

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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