# NTSB DEN87LA189: Aerospatiale SA316B, N48184, Red Lodge, MT, July 19, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 19, 1987, 11:30 local (17:30 UTC)
- Place: Red Lodge, MT
- Coordinates: 45.189594, -109.240455 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.1896&lon=-109.2405&mi=10
- Phase of flight: [Standing](https://openairdocs.org/ntsb-phases/150) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report May 9, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 17274
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN87LA189
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/17274/pdf
- Page: https://openairdocs.org/ntsb/DEN87LA189

## Sequence of events

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

- Roll over, standing - engine(s) operating
  - weather condition - crosswind (contributing factor)
  - weather condition - high wind (contributing factor)
  - weather condition - gusts (contributing factor)
  - preflight planning/preparation - poor, pilot in command (cause)
  - wind information - disregarded, pilot in command (cause)
  - rotor rpm - not attained, pilot in command (contributing factor)
- On ground/water encounter with terrain/water, standing - engine(s) operating
  - terrain condition - ground
  - terrain condition - mountainous/hilly

## Analysis

THE PLT SAID HE WAS GETTING READY TO TAKE OFF FROM A 9400-FT MSL LANDING ZONE A TOP A MOUNTAIN 7 MI SSW OF RED LODGE, MT. THE PLAT SAID THE HELICOPTER WAS POSITIONED ON A SLIGHT NORTH-SOUTH SLOPE AND POINTED TOWARDS THE WEST. THE WIND WAS FROM THE SOUTH GUSTING TO APRX 30 TO 40 KTS. THE PLT SAID THE ENG WAS RUNNING AND HE WAS ABOUT TO ENGAGE THE MAIN ROTOR. THE WIND SUDDENLY PITCHED THE HELICOPTER UP LATERALLY, LEFT TO RIGHT, AND BLEW IT OVER ON ITS SIDE.

## Aircraft

- Registration: [N48184](https://openairdocs.org/deregistered/N48184-2014-08-08), registration cancelled 2014-08-08, S/N 1906, built 1970 (OpenAirDocs)
- Reported make and model: AEROSPATIALE SA316B
- Registry model: [Aerospatiale SA316B ALOUETTE III](https://openairdocs.org/model/aerospatiale-sa316b-alouette-iii) (registry code 8680515) (OpenAirDocs)
- Registry engine: [Turbomeca ASTAZOU series](https://openairdocs.org/engine/turbomeca-astazou-series) (registry code 60020, turbo-shaft) (OpenAirDocs)
- Category: Helicopter
- Serial number: 1906
- Airframe hours: 4826
- Engines: TURBOMECA ARTOUSTE 111B 562 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Other work use, Part 133
- Operator: Pegasus Helicopters, Inc.
- Registered owner: Roberts Aircraft Company
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, June 29, 1987, 34 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 39; commercial; airplane ratings: single-engine land, multi-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 11,127 total, 3,000 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 180° at 35 knots, gusting 45
- Visibility: 120 statute miles
- Lowest ceiling: none
- Temperature: 50 °F
- Altimeter: 29.00 inHg

## 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 19870719041159A](https://openairdocs.org/incident/19870719041159A), Jul 19, 1987: Aerosp SA316B, Red Lodge, MT, Substantial damage. The helicopter was blown over by gusty winds.

## Other investigations on N48184 (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 LAX81DVA22](https://openairdocs.org/ntsb/LAX81DVA22), Feb 13, 1981: Aerospatle S316B (N48184), Dinky Creek, CA, substantial damage

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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