# NTSB SEA87FA194: Hughes 369D, N8613F, Seattle, WA, September 27, 1987

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Field investigation · Final report
- Date: September 27, 1987, 10:30 local (17:30 UTC)
- Place: Seattle, WA
- Coordinates: 47.730144, -122.339431 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.7301&lon=-122.3394&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor, 3 uninjured
- Status: Completed, report January 25, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 40539
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA87FA194
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40539/pdf
- Page: https://openairdocs.org/ntsb/SEA87FA194

## Sequence of events

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

- Loss of engine power, cruise - normal
  - reason for occurrence undetermined (cause)
- Forced landing, descent - emergency
  - autorotation
- Hard landing, landing - flare/touchdown
  - object - other person (contributing factor)
  - maneuver - performed
  - rotor rpm - not maintained

## Analysis

THE PLT RPRTD THAT WHILE HE WAS IN CRUISE FLIGHT AT ABOUT 1000', THE ENG LOST POWER. HE INITIATED AN AUTOROTATION TO AN ATHLETIC FIELD IN A CITY PARK. DRG HIS APCH, HE CHANGED HIS PLANNED TOUCHDOWN POINT SVRL TIMES DUE TO PERSONNEL ON THE FIELD. HE SAID THAT THIS RESULTED IN A LOSS OF AIRSPEED, & SUBSEQUENTLY, THE HELICOPTER LANDED HARD. DRG TOUCHDOWN, THE MAIN ROTOR BLADES FLEXED DOWNWARD & SEVERED THE TAIL BOOM. AN EXAM OF THE ENG REVEALED NO EVIDENCE OF A MECHANICAL MALFUNCTION THAT WOULD HAVE RESULTED IN A LOSS OF POWER.

## Aircraft

- Registration: [N8613F](https://openairdocs.org/deregistered/N8613F-1989-11-15), registration cancelled 1989-11-15, S/N 670127D (OpenAirDocs)
- Reported make and model: HUGHES 369D
- Registry model: [Hughes Helicopters HUGHES 369D](https://openairdocs.org/model/hughes-helicopters-hughes-369d) (registry code 4470706) (OpenAirDocs)
- Category: Helicopter
- Serial number: 670127D
- Airframe hours: 3129
- Engines: ALLISON 250-C20B 420 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Raymond D. Tenney
- Airworthiness certificate: Standard, Utility
- Last inspection: 100 hour, February 16, 1987, 64 hours before
- Departed: SHN, SHELDON, WA
- Destination: PAE, EVERETT, WA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 40; private; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 87 total, 18 in this make and model, 50 as pilot in command, 41 in the last 90 days, 22 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 20° at 7 knots
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: 57 °F, dew point 48 °F
- Altimeter: 30.00 inHg
- Observed at: BFI, 8 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 19870927080969A](https://openairdocs.org/incident/19870927080969A), Sep 27, 1987: Hughes 369D, Seattle, WA, Substantial damage. Made a hard autorotation landing when engine quit. Lost rotor RPM avoiding persons on athletic field.

## Other investigations on N8613F (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 SEA90FA005](https://openairdocs.org/ntsb/SEA90FA005), Oct 13, 1989: Hughes 369D (N8613F), Bothell, WA, destroyed, 1 fatal. Probable cause: THE PILOT FAILED TO DETERMINE WEATHER CONDITIONS BEFORE THE FLIGHT, HIS ATTEMPT TO FLY VFR IN IMC, AND HIS FAILURE TO MAINTAIN OBSTACLE CLEARANCE ALTITUDE. FACTORS IN THE ACCIDENT WERE THE LOW…

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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