# NTSB CHI76DEP10: Grum Amer AA1-A, N9251L, Portage, WI, July 20, 1975

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Closed
- Date: July 20, 1975
- Place: Portage, WI · PORTAGE, WI
- Location: 43.5490° N, 89.4659° W: Placed by OpenAirDocs: center of Portage, WI, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=43.5490&lon=-89.4659&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 2 minor
- Status: Completed, report November 25, 1975
- Report: Brief approved by the director
- NTSB case key (mKey): 150570
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI76DEP10
- Page: https://openairdocs.org/ntsb/CHI76DEP10

## NTSB brief

```
----------------------------------------------------------------------------------------------------------------------------
 FILE    DATE          LOCATION          AIRCRAFT DATA       INJURIES       FLIGHT                        PILOT DATA
                                                               F  S M/N     PURPOSE
----------------------------------------------------------------------------------------------------------------------------
3-3152  75/7/20    PORTAGE,WI          GRUM AMER AA1-A     CR-  0  0  1  NONCOMMERCIAL             ATP,FLIGHT INSTR., AGE
        TIME - 1730                    N9251L              PX-  0  0  1  PLEASURE/PERSONAL TRANSP  34, 4084 TOTAL HOURS, 108
                                       DAMAGE-SUBSTANTIAL  OT-  0  0  0                            IN TYPE, INSTRUMENT
                                                                                                   RATED.
        DEPARTURE POINT             INTENDED DESTINATION
          JANESVILLE,WI               PORTAGE,WI
        TYPE OF ACCIDENT                                         PHASE OF OPERATION
           ENGINE FAILURE OR MALFUNCTION                            IN FLIGHT: OTHER
           NOSE OVER/DOWN                                           LANDING: ROLL
        PROBABLE CAUSE(S)
           POWERPLANT - MISCELLANEOUS: POWERPLANT FAILURE FOR UNDETERMINED REASONS
           TERRAIN - HIDDEN OBSTRUCTIONS
        EMERGENCY CIRCUMSTANCES - PRECAUTIONARY LANDING OFF AIRPORT
        REMARKS- ENG SURGE.FLD APPEARED SMOOTH FM AIR,RUTS AND CLUMPS OF DIRT CAMOUFLAGED BY WEED CVR.
```

## Aircraft

- Registration: [N9251L](https://openairdocs.org/deregistered/N9251L-1975-10-03), registration cancelled 1975-10-03, S/N AA1A-0151 (OpenAirDocs)
- Reported make and model: GRUM AMER AA1-A
- Registry model: [American AA-1A](https://openairdocs.org/model/american-aa-1a) (registry code 0630710) (OpenAirDocs)
- Category: Airplane
- Engines: reciprocating
- Damage: Substantial damage

## 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 19750720025789A](https://openairdocs.org/incident/19750720025789A), Jul 20, 1975: Grumav AA1A, Portage, WI, Destroyed. Eng surge. Fld appeared smooth fm air,ruts and clumps of dirt camouflaged by weed CVR.

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.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.