# NTSB CHI91DEM06: Aeronca 11-AC, N86083, Central Lake, MI, July 11, 1991

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Final report
- Date: July 10, 1991, 20:00 local (Jul 11, 1991, 00:00 UTC)
- Place: Central Lake, MI
- Coordinates: 45.060981, -85.259986 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.0610&lon=-85.2600&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed, report December 4, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 14831
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI91DEM06
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14831/pdf
- Page: https://openairdocs.org/ntsb/CHI91DEM06

## Probable cause

A RESULT OF THE PILOT IN COMMAND NOT MAINTAINING AIRCRAFT CONTROL AND NOT PERFORMING REMEDIAL ACTION AFTER THE AIRPLANE ENTERED THE STEEP DESCENT. A FACTOR CONTRIBUTING TO THIS ACCIDENT WAS THE PILOT IN COMMAND'S LACK OF RECENT EXPERIENCE.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of control - in flight, takeoff - initial climb
  - lack of recent experience, pilot in command (contributing factor)
  - aircraft control - not maintained, pilot in command (cause)
  - remedial action - not performed, pilot in command (cause)
- In flight collision with terrain/water, descent - emergency
  - terrain condition - mountainous/hilly
  - terrain condition - ground

## Analysis

WITNESSES OBSERVED THE LIGHT, SINGLE ENGINED, AIRPLANE PERFORMING A CLIMB AFTER A TOUCH AND GO LANDING.  DURING THE CLIMB WITNESSES REPORTED THAT THE AIRPLANE SUDDENLY PITCHED STRAIGHT DOWN AND DESCENDED INTO THE TERRAIN.  AN ON SCENE INVESTIGATION DID NOT REVEAL ANY CONTROL, AIRFRAME, OR POWERPLANT CONDITIONS WHICH WOULD CONTRIBUTE TO SUCH AN UNCONTROLLED DESCENT.  THE AIRSTRIP HAD A 3 DEGREE DOWNSLOPE FROM THE CENTER OF THE RUNWAY TOWARD BOTH THE APPROACH AND DEPARTURE ENDS.  THE TERRAIN OFF THE DEPARTURE END OF THE RUNWAY DROPS SUDDENLY INTO AN APRX 300 FOOT DEEP VALLEY. INVESTIGATION REVEALED THE AIRPLANE'S LAST ANNUAL INSPECTION WAS 10 YEARS PRIOR TO THE ACCIDENT, THE PILOT'S STUDENT PILOT/THIRD CLASS MEDICAL CERTIFICATE WAS ISSUED APRX 13 YEARS PRIOR TO THE ACCIDENT, AND THAT THE PILOT'S LAST FLIGHT AS PIC WAS APRX TWO YEARS PRIOR TO THE ACCIDENT.

## Aircraft

- Registration: [N86083](https://openairdocs.org/deregistered/N86083-2001-01-10), registration cancelled 2001-01-10, S/N 11AC-507 (OpenAirDocs)
- Reported make and model: AERONCA 11-AC
- Registry model: [Aeronca 11AC](https://openairdocs.org/model/aeronca-11ac) (registry code 0191102) (OpenAirDocs)
- Category: Airplane
- Serial number: 11AC-507
- Airframe hours: 1700
- Engines: CONTINENTAL A&C 65 75 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: Terrance A. Grahm
- Registered owner: Terrance A. Grahm
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, June 26, 1981, 470 hours before
- Airport: NONE

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 40; medical: class 3, expired; toxicology performed; flight hours: 38 total, 38 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 20 statute miles
- Lowest ceiling: none

## 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 19910710026999A](https://openairdocs.org/incident/19910710026999A), Jul 10, 1991: Bbavia 11AC, Central Lake, MI, Destroyed, 1 fatal. No flights for 2 years and no checkout. Stalled on climbout from touch and go. No annual and no STC for auto fuel.

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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