# NTSB SEA74AS006: Boeing 737, N7381F, Missoula, MT, August 16, 1973

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Closed
- Date: August 16, 1973
- Place: Missoula, MT · MISSOULA, MT
- Location: 46.8721° N, 113.9940° W: Placed by OpenAirDocs: center of Missoula, MT, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=46.8721&lon=-113.9940&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious, 55 uninjured
- Status: Completed, report November 3, 1973
- Report: Brief approved by the director
- NTSB case key (mKey): 189821
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA74AS006
- Page: https://openairdocs.org/ntsb/SEA74AS006

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
1-0022  73/8/16    MISSOULA,MONT       BOEING 737          CR-  0  1  5  SCHED DOM PASSG SRV       AIRLINE TRANSPORT, AGE
        TIME - 0740                    N7381F              PX-  0  0 50                            52, 25586 TOTAL HOURS,
                                       DAMAGE-NONE         OT-  0  0  0                            UNK/NR IN TYPE,
                                                                                                   INSTRUMENT RATED.
        OPERATOR - FRONTIER AIRLINES,INC.
        DEPARTURE POINT             INTENDED DESTINATION
          MISSOULA,MONT               ST LOUIS,MO
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           MISCELLANEOUS                                            IN FLIGHT: NORMAL CRUISE
        PROBABLE CAUSE(S)
           SYSTEMS - FLIGHT CONTROL SYSTEMS: RUDDER AND RUDDER TAB CONTROL SYSTEM
        REMARKS- DEFECTIVE COIL IN B SYSTEM TRANSFER VALVE.
```

## Aircraft

- Registration: [N7381F](https://openairdocs.org/deregistered/N7381F-2013-05-07), registration cancelled 2013-05-07, S/N 20369, built 1970 (OpenAirDocs)
- Reported make and model: BOEING 737
- Registry model: [Boeing 737-2H4](https://openairdocs.org/model/boeing-737-2h4) (registry code 138448C) (OpenAirDocs)
- Registry engine: [Pratt & Whitney JT8D-9 series](https://openairdocs.org/engine/pratt-whitney-jt8d-9-series) (registry code 52048, turbo-jet) (OpenAirDocs)
- Category: Airplane
- Engines: turbo fan
- Damage: No damage

## Other investigations on N7381F (2)

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 DCA83AA021](https://openairdocs.org/ntsb/DCA83AA021), Mar 23, 1983: Boeing 737-2H4 (N7381F), Casper, WY, minor damage
- [NTSB DEN74AD009](https://openairdocs.org/ntsb/DEN74AD009), Aug 22, 1973: Boeing 737 (N7381F), Rapid City, SD, no 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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