CHI98LA032 · Cessna 421A
Cessna 421A · Accident: airframe, component or system failure en route
From Fun-Air Airport (WI46) to Poplar Grove Airport (C77)
Event
- NTSB case
- CHI98LA032
- 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 421A
- Aircraft type
- Cessna 421
- 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
- N2957Q
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Fun-Air Airport (WI46)To Poplar Grove Airport (C77), Poplar Grove, IL
- 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 · climb to 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
- Flight control, elevator tab › Flutter
- Miscellaneous, bolt/nut/fastener/clamp/spring › Separation
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
On climb out at 11,000 feet at 700 feet per minute rate of climb on autopilot, the pilot heard a loud bang and felt a 'rapid vibration in the control yoke.' The pilot reported pitch trim was not available and said he checked the engines for proper operations. The flight landed without further incident. Examination of the aircraft revealed substantial damage to the right elevator and trim tab. The rear trim tab linkage bolt was missing and there was little damage to the yoke or trim tab bushing. Paint transfer marks were found on the trim tab from the elevator. An undersized cotter pin was found in the forward linkage bolt.
Probable cause
the elevator trim tab bolt backed out, allowing the trim tab to flutter, and destroy the elevator. The factors involved were improper annual inspection by the maintenance personnel, and the inadequate aircraft preflight done by the pilot.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI98LA032
- Event ID
- 20001208X09144
- Case number
- CHI98LA032
- 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: a6f4fdccc228f3670a38d4863cd89ade653c531b749fd5937253cb6357ad5f9a; retrieved 2026-09-22T18:12:59.470Z.