WPR22LA099 · Aeronca 11AC
Aeronca 11AC · Accident en route
From University Airport (KEDU) to Charles M. Schulz Sonoma County Airport (KSTS)
Event
- NTSB case
- WPR22LA099
- 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
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- 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 11AC
- 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
- N9500E
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From University Airport (KEDU), Davis, CATo Charles M. Schulz Sonoma County Airport (KSTS), Santa Rosa, CA
- Aircraft age
- About 76 years (built 1946)
- 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
- En route · cruise
- Defining eventThe 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
- Unknown or undetermined
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Aircraft power plant
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot was flying the airplane to an airport about 48 miles from the departure airport when, 30 minutes after departure while in cruise flight, the engine lost all power. The pilot then verified engine controls were at their correct positions and adjusted the carburetor heat setting. There was no change in engine power, so he made a mayday call and landed the airplane in an open field, during which the airplane sustained substantial damage to the lower fuselage. A postaccident examination of the engine revealed that both magnetos produced a weak spark on all ignition leads when the propeller was rotated by hand. The left magneto was found to be in poor condition and did not function within the manufacturer’s specifications. Internal examination of the left magneto revealed that the distributor axle bearing had failed, and the distributor gear was missing about half of its gear teeth. The right magneto was found in poor overall condition and was missing about 6 distributor gear teeth; however, it did function within the manufacturer’s specifications. A review of maintenance records revealed no indication that the left and right magnetos were serviced, to include inspections or overhauls, since the engine’s last overhaul 15 years (or about 400 hours) before the accident. While the left magneto was not functioning within the manufacturers specifications, and the right magneto functioned within the manufacturers specifications, it would not result a total loss of engine power. The reason for the total loss of engine power could not be determined.
Probable cause
The loss of engine power for undetermined reasons, which resulted in an off-airport landing on unimproved terrain.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR22LA099
- Event ID
- 20220216104651
- Case number
- WPR22LA099
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
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: investigation status, cause areas. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 191552a28f26256e9a4aca18a6c549029e71a2db3f98cf6e7b036d1b311fa94e; retrieved 2026-09-16T14:57:57.243Z.