Bemidji Aviation Services Beech U-8F accident
Beech U-8F · Accident: explosion (non-impact) while standing
From Goodland Municipal Airport (GLD) to Denver International Airport (DEN)
Event
- NTSB case
- CEN21LA274
- 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
- Event fatalities
- Unknown
- 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
- Charter & commuter
- 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
Beech U-8F
- Aircraft type
- Beechcraft U-8
- 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
- N62069
- Operator
- Bemidji Aviation Services
- Onboard fatalities
- Unknown
- Route
- From Goodland Municipal Airport (GLD), Goodland, KSTo Denver International Airport (DEN), Denver, CO
- Aircraft age
- About 59 years (built 1962)
- 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 135: Air Taxi & Commuter
- 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
- Standing · engine(s) start-up
- 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
- Explosion (non-impact)
- 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 systems
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot heard a loud bang while starting the right engine and noticed flames exiting the right wing. An airport surveillance camera captured a wing explosion that lasted about 1 second, which substantially damaged the right wing.
Examination revealed that the right wing outboard aft fuel bladder was brittle, with several holes due to age-related oxidation, and electrical wiring to the navigation lights was chafed in two locations, with evidence of electrical arcing. Review of maintenance records indicated that the airplane was inspected about 50 hours before the accident; the inspection included checking the fuel tanks for leakage, and electrical wiring for chafing. Based on the condition of the fuel bladder and wiring, it is likely that the most recent inspection was inadequate.
About 2 years before the accident, the airplane’s left wing exploded due to ignition of fuel vapor. Following the most recent wing explosion accident, the operator instituted several maintenance protocols to aid in detection of a fuel leak, including top-off of the fuel system in conjunction with the wing inspection procedure checklist or unscheduled fuel system maintenance.
Probable cause
Maintenance personnel’s inadequate inspection of the airplane, which failed to detect and correct chafed electrical wiring and a degraded fuel bladder with holes, which resulted in ignition of fuel vapor and a right wing explosion.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN21LA274
- Event ID
- 20210617103280
- Case number
- CEN21LA274
- 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: local date, investigation status, cause areas. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2021-06-17.
- API snapshot SHA-256: af6fc4fe38e16bb8faf654d5025098f3c30d5e6d31abb4fb5879a6504e7be365; retrieved 2026-09-16T14:10:46.684Z.