# NTSB UNK64X2139: Sikorsky S55, N873Z, Holopaw, FL, June 5, 1964

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: June 5, 1964
- Place: Holopaw, FL · HOLOPAW, FL
- Location: 28.1358° N, 81.0762° W: Placed by OpenAirDocs: center of Holopaw, FL, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=28.1358&lon=-81.0762&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report November 20, 1964
- Report: Brief approved by the director
- NTSB case key (mKey): 183684
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=UNK64X2139
- Page: https://openairdocs.org/ntsb/UNK64X2139

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
2-0540   64/6/5  NR.HOLOPAW FLORIDA    SIKORSKY S55        CR-  0  0  1  COMMERCIAL                COMMERCIAL, AGE 28, 2100
        TIME - 1115                    N873Z               PX-  0  0  0  CONSTRUCTION              TOTAL HOURS, 1000 IN
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            TYPE, NOT INSTRUMENT
                                                                                                   RATED.
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           ENGINE FAILURE OR MALFUNCTION                            TAKEOFF: VERTICAL
           ROLL OVER                                                LANDING: POWER-OFF AUTOROTATIVE LANDING
        PROBABLE CAUSE(S)
           ROTORCRAFT - TRANSMISSION ROTOR DRIVE SYSTEM: CLUTCH ASSEMBLY
           MISCELLANEOUS ACTS,CONDITIONS - LACK OF LUBRICATION-SPECIFIC PART,NOT SYSTEM
           PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: IMPROPER MAINTENANCE (MAINTENANCE PERSONNEL)
        COMPLETE POWER LOSS - COMPLETE ENGINE FAILURE/FLAMEOUT-1 ENGINE
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
        REMARKS- CLUTCH FREE WHEEL UNIT ROLLERS P/N S-14-35-2523 HAD FLAT AND BADLY ABRADED AREAS
```

## Aircraft

- Registration: [N873Z](https://openairdocs.org/deregistered/N873Z-2018-05-21), registration cancelled 2018-05-21, S/N 55372, built 1953 (OpenAirDocs)
- Reported make and model: SIKORSKY S55
- Registry model: [Sikorsky S-55B](https://openairdocs.org/model/sikorsky-s-55b) (registry code 8141604) (OpenAirDocs)
- Registry engine: [Wright C7BA series](https://openairdocs.org/engine/wright-c7ba-series) (registry code 67017, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Engines: reciprocating
- Damage: 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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