# NTSB DEN81FA068: Cessna T210L, N94136, Big Timber, MT, September 25, 1981

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Closed
- Date: September 25, 1981
- Place: Big Timber, MT · BIG TIMBER, MT
- Location: 45.8348° N, 109.9483° W: Placed by OpenAirDocs: center of Big Timber, MT, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=45.8348&lon=-109.9483&mi=10
- Phase of flight: [Uncontrolled descent](https://openairdocs.org/ntsb-phases/650) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed, report May 13, 1982
- Report: Brief approved by the director
- NTSB case key (mKey): 122724
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN81FA068
- Page: https://openairdocs.org/ntsb/DEN81FA068

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-3615  81/9/25    BIG TIMBER,MT       CESSNA T210L        CR-  1  0  0  NONCOMMERCIAL             PRIVATE, AGE 40, 3700
        TIME - 1830                    N94136              PX-  0  0  0  BUSINESS                  TOTAL HOURS, 500 IN TYPE,
                                       DAMAGE-DESTROYED    OT-  0  0  0                            INSTRUMENT RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          BOISE,ID                    BILLINGS,MT
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           AIRFRAME FAILURE: IN FLIGHT                              IN FLIGHT: UNCONTROLLED DESCENT
        PROBABLE CAUSE(S)
           POWERPLANT - ENGINE ACCESSORIES: VACUUM PUMPS
           MISCELLANEOUS ACTS,CONDITIONS - MATERIAL FAILURE
           PILOT IN COMMAND - SPATIAL DISORIENTATION
           PILOT IN COMMAND - EXCEEDED DESIGNED STRESS LIMITS OF AIRCRAFT
        FACTOR(S)
           WEATHER - RAIN
           AIRFRAME - WINGS: SPARS
           MISCELLANEOUS ACTS,CONDITIONS - OVERLOAD FAILURE
           MISCELLANEOUS ACTS,CONDITIONS - SEPARATION IN FLIGHT
        WEATHER BRIEFING - NO RECORD OF BRIEFING RECEIVED
        SKY CONDITION                                            CEILING AT ACCIDENT SITE
          OVERCAST                                                  1000
        VISIBILITY AT ACCIDENT SITE                              PRECIPITATION AT ACCIDENT SITE
          5 OR OVER(UNLIMITED)                                     RAIN
        OBSTRUCTIONS TO VISION AT ACCIDENT SITE                  TEMPERATURE-F
          NONE                                                      41
        WIND DIRECTION-DEGREES                                   WIND VELOCITY-KNOTS
          220                                                       14
        TYPE OF WEATHER CONDITIONS                               TYPE OF FLIGHT PLAN
          IFR                                                      IFR
        REMARKS- VACUUM PUMP'S FLEXIBLE DRIVESHAFT COUPLING FAILED.
```

## Aircraft

- Registration: [N94136](https://openairdocs.org/deregistered/N94136-2013-05-22), registration cancelled 2013-05-22, S/N 21060514, built 1974 (OpenAirDocs)
- Reported make and model: CESSNA T210L
- Registry model: [Cessna T210L](https://openairdocs.org/model/cessna-t210l) (registry code 2073449) (OpenAirDocs)
- Registry engine: [Continental TSIO-520 series](https://openairdocs.org/engine/continental-tsio-520-series) (registry code 17040, reciprocating) (OpenAirDocs)
- Category: Airplane
- 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 19810925063009A](https://openairdocs.org/incident/19810925063009A), Sep 25, 1981: Cessna T210L, Big Timber, MT, Destroyed. Pilot lost control of aircraft in IMC when vacuum pump failed. Model airborne 212CW

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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