# NTSB DEN77FA019: Sikorsky S-64E, N6965R, Cowdrey, CO, December 13, 1976

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Closed
- Date: December 13, 1976
- Place: Cowdrey, CO · COWDREY, CO
- Location: 40.8597° N, 106.3131° W: Placed by OpenAirDocs: center of Cowdrey, CO, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=40.8597&lon=-106.3131&mi=10
- Phase of flight: [Uncontrolled descent](https://openairdocs.org/ntsb-phases/650) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious, 2 minor
- Status: Completed, report May 19, 1977
- Report: Brief approved by the director
- NTSB case key (mKey): 149705
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN77FA019
- Page: https://openairdocs.org/ntsb/DEN77FA019

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-4084  76/12/13 NR.COWDREY,CO         SIKORSKY S-64E      CR-  0  1  2  COMMERCIAL                COMMERCIAL, AGE 35, 4584
        TIME - 0945                    N6965R              PX-  0  0  0  CONSTRUCTION              TOTAL HOURS, 2077 IN
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            TYPE, NOT INSTRUMENT
                                                                                                   RATED.
        DEPARTURE POINT             INTENDED DESTINATION
         COWDREY,CO                   LOCAL
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           COLLISION WITH GROUND/WATER: UNCONTROLLED                IN FLIGHT: UNCONTROLLED DESCENT
        PROBABLE CAUSE(S)
           PILOT IN COMMAND - INADEQUATE PREFLIGHT PREPARATION AND/OR PLANNING
           PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: INADEQUATE MAINTENANCE AND INSPECTION
           SYSTEMS - FLIGHT CONTROL SYSTEMS: FLIGHT CONTROL BOOST SYSTEMS, HYDRAULIC
           MISCELLANEOUS ACTS,CONDITIONS - IMPROPERLY INSTALLED
           SYSTEMS - HYDRAULIC SYSTEM: RESERVOIR,LINES,FITTINGS
           MISCELLANEOUS ACTS,CONDITIONS - LEAK/LEAKAGE
           MISCELLANEOUS ACTS,CONDITIONS - LOOSE,PART/FITTING
        EMERGENCY CIRCUMSTANCES - FORCED LANDING OFF AIRPORT ON LAND
        REMARKS- PRESSURE AND RETURN HYD LINES TO LEFT LATERAL SERVO REVERSED HYD LEAK DEVELOPED IN FLIGHT
```

## Aircraft

- Registration: [N6965R](https://openairdocs.org/deregistered/N6965R-1999-04-01), registration cancelled 1999-04-01, S/N 64060, built 1968 (OpenAirDocs)
- Reported make and model: SIKORSKY S-64E
- Registry model: [Sikorsky S-64E](https://openairdocs.org/model/sikorsky-s-64e) (registry code 8142604) (OpenAirDocs)
- Category: Helicopter
- Engines: turbo shaft
- Damage: Substantial damage

## 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 19761213042389A](https://openairdocs.org/incident/19761213042389A), Dec 13, 1976: Skrsky S64E, Cowdrey, WY, Substantial damage. Pressure and return hyd lines to left lateral servo reversed hyd leak developed in flight

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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