# NTSB SEA75FYE11: Bell 47G-2A, N88AR, Mercer Isl, WA, August 11, 1974

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Closed
- Date: August 11, 1974
- Place: Mercer Isl, WA · MERCER ISL, WA
- Location: 47.5640° N, 122.2312° W: Placed by OpenAirDocs: center of Mercer Island, WA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=47.5640&lon=-122.2312&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious, 1 minor, 1 uninjured
- Status: Completed, report January 30, 1975
- Report: Brief approved by the director
- NTSB case key (mKey): 138619
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA75FYE11
- Page: https://openairdocs.org/ntsb/SEA75FYE11

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-4069  74/8/11    MERCER ISL,WASH     BELL 47G-2A         CR-  0  0  1  COMMERCIAL                COMMERCIAL, FL.INSTR.,
        TIME - 1346                    N88AR               PX-  0  1  1  MAPPING/PHOTO             AGE 35, 1470 TOTAL HOURS,
                                       DAMAGE-DESTROYED    OT-  0  0  0                            870 IN TYPE, NOT
                                                                                                   INSTRUMENT RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          SEATTLE,WASH                LOCAL
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           PROPELLER/ROTOR FAILURE: TAIL ROTOR                      IN FLIGHT: NORMAL CRUISE
           COLLISION WITH GROUND/WATER: CONTROLLED                  LANDING: LEVEL OFF/TOUCHDOWN
        PROBABLE CAUSE(S)
           ROTORCRAFT - TRANSMISSION ROTOR DRIVE SYSTEM: TAIL ROTOR GEAR BOX
           MISCELLANEOUS ACTS,CONDITIONS - MATERIAL FAILURE
        FACTOR(S)
           MISCELLANEOUS ACTS,CONDITIONS - SEPARATION IN FLIGHT
           MISCELLANEOUS ACTS,CONDITIONS - AIRCRAFT CAME TO REST IN WATER
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON WATER
        REMARKS- T/R GR BOX SEPARATED FOR UNDET REASON.SANK IN LAKE.
```

## Aircraft

- Registration: [N88AR](https://openairdocs.org/aircraft/N88AR), registered now, S/N 2046, built 1957 (OpenAirDocs)
- Reported make and model: BELL 47G-2A
- Registry model: [Bell 47G-2](https://openairdocs.org/model/bell-47g-2) (registry code 1181008) (OpenAirDocs)
- Registry engine: [Lycoming VO-435 series](https://openairdocs.org/engine/lycoming-vo-435-series) (registry code 41525, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Engines: reciprocating
- Damage: Destroyed

## 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 19740811025939A](https://openairdocs.org/incident/19740811025939A), Aug 11, 1974: Bell 47G2A, Mercer Isl, WA, Substantial damage. T/r gr box separated for undet reason. Sank in lake.

## Other investigations on N88AR (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 MIA85LA223](https://openairdocs.org/ntsb/MIA85LA223), Aug 1, 1985: Bell 47G-2 (N88AR), Ochopee, FL, 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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