ANC93FA070 · Cessna 320
Aeromap US Cessna 320 · Accident: airframe, component or system failure en route
From Merrill Field (MRI) to Merrill Field (MRI)
Event
- NTSB case
- ANC93FA070
- 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
- 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
Cessna 320
- Aircraft type
- Cessna 320
- 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
- N4198T
- Operator
- Aeromap US
- Onboard fatalities
- Unknown
- Route
- From Merrill Field (MRI)To Merrill Field (MRI)
- 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
- En route · cruise
- 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
- Airframe, component or system failure
- 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
- Electrical system › Undetermined
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
THE PILOT SAID THAT DURING FLIGHT, HE ENCOUNTERED AN OVERVOLTAGE CONDITION & TURNED OFF THE ELECTRICAL MASTER SWITCH. HE NOTED THAT THE VHF RADIO CIRCUIT BREAKER HAD TRIPPED & THE TURN & BANK INDICATOR SMOKED. HE SAID THAT ABOUT 10 MILES FROM THE AIRPORT, HE TURNED THE MASTER SWITH BACK ON & TRIED TO RESET THE CIRCUIT BREAKER, BUT AGAIN HE NOTED SMOKE IN THE COCKPIT. HE SAID THE LANDING GEAR EXTENDED VERY FAST & HARD, BUT IT DID NOT LOCK. WHEN HE ATTEMPTED TO FOLLOW THE EMERGENCY GEAR EXTENSION PROCEDURE, THE CRANK DID NOT WORK. THE MAIN GEAR COLLAPSED DURING LANDING. AN EXAM OF THE ELECTRICAL SYSTEM DISCLOSED A CHARRED & EXPANDED BATTERY. THE DOWN LIMIT SWITCH FOR THE LANDING GEAR MOTOR HAD BROKEN FROM ITS MOUNT BY THE UPPER BELL CRANK TRAVELING BEYOND THE DOWN LIMIT; A TEARDOWN OF THE LANDING GEAR ACTUATOR ASSEMBLY DISCLOSED EVIDENCE OF OVERTRAVEL. THE ALTERNATORS, VOLTAGE REGULATORS & OVER VOLTAGE RELAY ALL TESTED WITHIN ALLOWABLE LIMITS.
Probable cause
AN UNDETERMINED FAILURE THAT RESULTED IN AN OVERVOLTAGE CONDITION OF THE ELECTRICAL SYSTEM, OVERHEATING OF THE BATTERY, OVERDRIVE (OVERTORQUE) OF THE LANDING GEAR EXTENSION SYSTEM, A DISCONNECT OF THE EMERGENCY EXTENSION SYSTEM, AND A SUSBSEQUENT COLLAPSE OF THE MAIN GEAR WHEN IT COULD NOT BE LOCKED IN THE EXTENDED POSITION.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC93FA070
- Event ID
- 20001211X12260
- Case number
- ANC93FA070
- 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: investigation status. 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: b8ec8f974db147bf9c338cc49aa681152d55b8576157fbf229a19b9693440fc4; retrieved 2026-09-23T02:02:41.394Z.