# NTSB UNK64X3438: Boeing PT17, N56551, Coolidge, AZ, August 17, 1964

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: August 17, 1964
- Place: Coolidge, AZ · COOLIDGE, AZ
- Location: 32.9778° N, 111.5176° W: Placed by OpenAirDocs: center of Coolidge, AZ, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=32.9778&lon=-111.5176&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report October 21, 1964
- Report: Brief approved by the director
- NTSB case key (mKey): 182344
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=UNK64X3438
- Page: https://openairdocs.org/ntsb/UNK64X3438

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-2379  64/8/17    COOLIDGE ARIZ       BOEING PT17         CR-  0  0  1  COMMERCIAL                COMMERCIAL, AGE 49, 5530
        TIME - 1030                    N56551              PX-  0  0  0  ASSOC CROP CTL ACTIVITY   TOTAL HOURS, 1000 IN
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            TYPE, NOT INSTRUMENT
                                                                                                   RATED.
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           GROUND-WATER LOOP-SWERVE                                 LANDING: ROLL
           NOSE OVER/DOWN                                           LANDING: ROLL
        PROBABLE CAUSE(S)
           PILOT IN COMMAND - IMPROPER OPERATION OF BRAKES AND/OR FLIGHT CONTROLS
         SPECIAL DATA
          TOTAL HOURS IN CROP CONTROL - 1500                       KIND OF OPERATION - SPRAYING CROPS
          KIND OF CROP - COTTON                                    TYPE OF CHEMICAL USED - UNKNOWN/NOT REPORTED
          PILOT' S SEAT BELT -FASTENED-PROPERLY                    GLOVES - NOT USED
          GOGGLES - USED                                           CRASH HELMET - AVAILABLE-NOT USED
          COCKPIT CRASHPAD - NOT INSTALLED                         CRASH BAR - NOT INSTALLED
          TANK/HOPPER-LOCATION - FORWARD OF PILOT                  ELEVATION-AREA BEING TREATED-FEET -  1400
```

## Aircraft

- Registration: [N56551](https://openairdocs.org/aircraft/N56551), registered now, S/N 75-3926 (OpenAirDocs)
- Reported make and model: BOEING PT17
- Registry model: [Boeing A75](https://openairdocs.org/model/boeing-a75) (registry code 1380108) (OpenAirDocs)
- Registry engine: [Continental W670 series](https://openairdocs.org/engine/continental-w670-series) (registry code 17018, reciprocating) (OpenAirDocs)
- Category: Airplane
- Engines: reciprocating
- Damage: Substantial damage

## Other investigations on N56551 (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 SEA07LA213](https://openairdocs.org/ntsb/SEA07LA213), Jul 21, 2007: Boeing A-75 (N56551), Spokane, WA, substantial damage. Probable cause: The locking/seizing of a main landing gear brake mechanism during the landing roll.
- [NTSB LAX67D0057](https://openairdocs.org/ntsb/LAX67D0057), Jul 27, 1966: Stearman A75 (N56551), Dateland, AZ, 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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