# NTSB UNK65X0610: Aero Cmdr 520, N4172B, Chicago, IL, November 8, 1964

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Closed
- Date: November 8, 1964
- Place: Chicago, IL · CHICAGO, IL
- Location: 41.8500° N, 87.6501° W: Placed by OpenAirDocs: center of Chicago, IL, within about 9 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=41.8500&lon=-87.6501&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report February 24, 1965
- Report: Brief approved by the director
- NTSB case key (mKey): 181177
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=UNK65X0610
- Page: https://openairdocs.org/ntsb/UNK65X0610

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-3847   64/11/8   CHICAGO ILL         AERO CMDR 520       CR-  0  0  1  NONCOMMERCIAL             AIRLINE TRANSPORT, AGE
        TIME - 1800                    N4172B              PX-  0  0  1  CORP/EXEC                 39, 8500 TOTAL HOURS,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            1900 IN TYPE, INSTRUMENT
                                                                                                   RATED.
        NAME OF AIRPORT - OHARE FIELD
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           GROUND-WATER LOOP-SWERVE                                 LANDING: ROLL
           GEAR COLLAPSED                                           LANDING: ROLL
        PROBABLE CAUSE(S)
           AIRFRAME - LANDING GEAR: BRAKING SYSTEM (NORMAL SYSTEM)
           MISCELLANEOUS ACTS,CONDITIONS - MATERIAL FAILURE
           PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: IMPROPER MAINTENANCE (MAINTENANCE PERSONNEL)
           PERSONNEL - MAINTENANCE,SERVICING,INSPECTION: INADEQUATE INSPECTION OF AIRCRAFT (MAINTENANCE PERSONNEL)
        FACTOR(S)
           MISCELLANEOUS ACTS,CONDITIONS - OVERLOAD FAILURE
        REMARKS- RIGHT BRAKE LOCKED DURING LANDING ROLL.
```

## Aircraft

- Registration: [N4172B](https://openairdocs.org/deregistered/N4172B-2014-10-06), registration cancelled 2014-10-06, S/N 520-78, built 1953 (OpenAirDocs)
- Reported make and model: AERO CMDR 520
- Registry model: [Aero Commander 520](https://openairdocs.org/model/aero-commander-520) (registry code 0141202) (OpenAirDocs)
- Registry engine: [Lycoming GO-435](https://openairdocs.org/engine/lycoming-go-435) (registry code 41520, reciprocating) (OpenAirDocs)
- Category: Airplane
- Engines: reciprocating
- Damage: Substantial damage
- Airport: Ohare Field

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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