CHI91DEM06 · Aeronca 11-AC
Aeronca 11-AC · Accident: loss of control in flight during initial climb
Event
- NTSB case
- CHI91DEM06
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 1 · all aircraft and ground
- Ground fatalities
- 0
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Aeronca 11-AC
- Aircraft type
- Aeronca 11
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N86083
- Operator
- Terrance A. Grahm · private individual
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Initial climb
- First occurrenceThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Loss of control in flight
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Pilot in command › Aircraft control, not maintained
- Pilot in command › Remedial action, not performed
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
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.
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.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI91DEM06
- Event ID
- 20001212X17471
- Case number
- CHI91DEM06
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: local date, investigation status. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 1991-07-11.
- API snapshot SHA-256: 88d9cde28402f0688885f3fe24baab6d7b1bc8bba21f1153a2b98e340e7a63cc; retrieved 2026-09-21T01:42:52.208Z.