CHI00LA178 · Weatherly 201C
Weatherly 201C · Accident: airframe, component or system failure while maneuvering
From Trinity Health Heliport (19ND) to an unrecorded destination
Event
- NTSB case
- CHI00LA178
- 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
Weatherly 201C
- Aircraft type
- Weatherly 201
- 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
- N9228W
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Trinity Health Heliport (19ND), NDTo 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 137: Agricultural
- 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
- Maneuvering · aerial application
- 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
- Destroyed
Cause areas
- Wing, spar › Fatigue
- Wing, spar › Separation
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The airplane was destroyed by impact with terrain while maneuvering. The right wing was found detached and was found on the township road. A post crash fire occurred in the fuselage and left wing. The North Dakota Highway Patrol report stated, "The wing came off the plane and the plane then crashed approx. 396' west of the township road in a field of flax. The plane came to rest and was burning approx 471' west of the township road." The pilot sustained fatal injuries. The annual inspection was completed on May 1, 2000. The airplane had 343 hours since its last annual inspection and "5,400+" hours total time. Sections of the separated right wing and its mating surface were cut away and shipped to the NTSB's Materials Laboratory for detailed examination. Crack arrest lines and striations were found in the fracture area. Corrosion was observed on portions of the spar cap fracture surface. Circumferential grooves were observed. The upper and lower sides of the spar cap hole and adjacent fracture surfaces using scanning electron microscopy indicate fatigue origins initiating from corrosion pits on the hole surface. Subsequent to the accident the manufacturer issued a mandatory service bulletin to inspect the spar for cracks before the next flight and subsequent inspections accomplished at intervals no greater than 500 hours of flight.
Probable cause
the wing spar fatigue and wing separation while maneuvering. A factor was that the fatigue was not detected by the mechanic during the last annual inspection.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI00LA178
- Event ID
- 20001212X21192
- Case number
- CHI00LA178
- 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: 2b528570be4351c6d0a8a2e9adb1cab52de995217d8bc24fbb4cfc1587d0bd1a; retrieved 2026-09-20T21:06:07.594Z.