# NTSB MIA89LA240: Bell 47G-2, N37870, Cayey, PR, September 3, 1989

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 3, 1989, 17:30 local (21:30 UTC)
- Place: Cayey, PR
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report September 5, 1991
- Report: Approved by Office Director
- NTSB case key (mKey): 32495
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA89LA240
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/32495/pdf
- Page: https://openairdocs.org/ntsb/MIA89LA240

## Probable cause

LOSS OF ENGINE POWER FOR AN UNKNOWN REASON.  A FACTOR RELATED TO THE ACCIDENT WAS: THE PRESENCE OF TREES IN THE EMERGENCY LANDING AREA.

## Sequence of events

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

- Loss of engine power, cruise
  - reason for occurrence undetermined (cause)
- Forced landing, descent - emergency
  - autorotation
- On ground/water collision with object, landing - flare/touchdown
  - object - tree(s) (contributing factor)

## Analysis

THE PVT PLT HAD A SINGLE ENG LAND RATING & WAS TRAINING AS A STUDENT FOR A HELICOPTER RATING. WHILE ON A LOCAL FLT AT ABOUT 300 FT AGL, HE NOTED A DECREASE IN ROTOR RPM. HE RPRTD THAT HE TRIED TO INCREASE THE RPM BY ADVANCING THE THROTTLE, BUT THERE WAS NO RESPONSE. SUBSEQUENTLY, THE PLT LANDED THE HELICOPTER IN TREES, WHEN HE WAS UNABLE TO REACH A CLEARING. NO REASON WAS FOUND FOR THE RPRTD LOSS OF POWER.

## Aircraft

- Registration: [N37870](https://openairdocs.org/deregistered/N37870-2014-11-26), registration cancelled 2014-11-26, S/N 47-1965-2, built 1980 (OpenAirDocs)
- Reported make and model: BELL 47G-2
- Registry model: [Bell-Huddleston 47G2](https://openairdocs.org/model/bell-huddleston-47g2) (registry code 1181074) (OpenAirDocs)
- Registry engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: 47-1965-3
- Airframe hours: 1374
- Engines: LYCOMING VO-435-A 260 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Martinez,Juan
- Registered owner: Juan F Martinez
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, June 15, 1989, 25 hours before
- Departed: CAROLINA, PR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 38; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 179 total, 57 in this make and model, 83 as pilot in command, 25 in the last 90 days, 3 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 100° at 8 knots
- Visibility: 12 statute miles
- Lowest ceiling: 25,000 ft broken
- Temperature: 84 °F, dew point 77 °F
- Altimeter: 29.00 inHg
- Observed at: SJU, 27 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 19890903033409A](https://openairdocs.org/incident/19890903033409A), Sep 3, 1989: Bell 47G2, Cayey, Puerto Rico, Substantial damage. Lost rotor RPM and split needles with no power response. Autorotated into trees.

## Other investigations on N37870 (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 MIA93LA076](https://openairdocs.org/ntsb/MIA93LA076), Feb 28, 1993: Huddleston-Bell 47G2 (N37870), Rio Grande, PR, substantial damage. Probable cause: POOR IN-FLIGHT PLANNING BY THE PILOT-IN-COMMAND. CONTRIBUTING TO THE ACCIDENT WAS THE FLIGHT'S LACK OF TOTAL EXPERIENCE.

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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