# NTSB OAK78FVD13: Grumman AA1-B, N9952L, Concord, CA, January 25, 1978

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Closed
- Date: January 25, 1978
- Place: Concord, CA · CONCORD, CA
- Location: 37.9722° N, 122.0016° W: Placed by OpenAirDocs: center of Concord, CA, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=37.9722&lon=-122.0016&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report February 15, 1978
- Report: Brief approved by the director
- NTSB case key (mKey): 143545
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=OAK78FVD13
- Page: https://openairdocs.org/ntsb/OAK78FVD13

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-0070  78/1/25  NR.CONCORD,CA         GRUMMAN AA1-B       CR-  0  0  1  NONCOMMERCIAL             PRIVATE, AGE 48, 101
        TIME - 1120                    N9952L              PX-  0  0  0  PRACTICE                  TOTAL HOURS, ALL IN TYPE,
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            NOT INSTRUMENT RATED.
        NAME OF AIRPORT - BUCHANAN FIELD
        DEPARTURE POINT             INTENDED DESTINATION
         CONCORD,CA                   LOCAL
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           COLLISION WITH GROUND/WATER: CONTROLLED                  IN FLIGHT: DESCENDING
        PROBABLE CAUSE(S)
           PILOT IN COMMAND - CONTINUED VFR FLIGHT INTO ADVERSE WEATHER CONDITIONS
           PILOT IN COMMAND - FAILED TO FOLLOW APPROVED PROCEDURES,DIRECTIVES,ETC.
        FACTOR(S)
           WEATHER - FOG
        WEATHER BRIEFING - NO RECORD OF BRIEFING RECEIVED
        SKY CONDITION                                            CEILING AT ACCIDENT SITE
          UNKNOWN/NOT REPORTED                                     UNKNOWN/NOT REPORTED
        VISIBILITY AT ACCIDENT SITE                              PRECIPITATION AT ACCIDENT SITE
          2 MILES OR LESS                                          NONE
        OBSTRUCTIONS TO VISION AT ACCIDENT SITE                  TYPE OF WEATHER CONDITIONS
          FOG                                                      IFR
        TYPE OF FLIGHT PLAN
          NONE
        REMARKS- HIT HILL AFTER DESCENDING BELOW ASSIGNED ALTITUDE WHILE WAITING FOR SPECIAL VFR CLEARANCE.
```

## Aircraft

- Registration: [N9952L](https://openairdocs.org/deregistered/N9952L-2009-09-18), registration cancelled 2009-09-18, S/N AA1B-0252, built 1973 (OpenAirDocs)
- Reported make and model: GRUMMAN AA1-B
- Registry model: [Grumman American Avn. AA-1B](https://openairdocs.org/model/grumman-american-avn-aa-1b) (registry code 3960103) (OpenAirDocs)
- Registry engine: [Lycoming 0-235 series](https://openairdocs.org/engine/lycoming-0-235-series) (registry code 41505, 4 cycle) (OpenAirDocs)
- Category: Airplane
- Engines: reciprocating
- Damage: Substantial damage
- Airport: Buchanan Field

## 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 19780125000689A](https://openairdocs.org/incident/19780125000689A), Jan 25, 1978: Grumav AA1B, Concord, CA, Substantial damage. Hit hill after descending below assigned altitude while waiting fpecial VFR clearance.

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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