CHI96LA235 · Beech B35
Beech B35 · Accident: airframe, component or system failure en route
From Jefferson City Memorial Airport (JEF) to Spirit of St Louis Airport (SUS)
Event
- NTSB case
- CHI96LA235
- 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
Beech B35
- Aircraft type
- Beechcraft 35
- 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
- N5001C
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Jefferson City Memorial Airport (JEF), Jefferson City, MOTo Spirit of St Louis Airport (SUS)
- 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
- Flight control, elevator tab › Improper
- Flight control, ruddervator › Flutter
- Flight control, ruddervator › Out of balance
- Other maintenance personnel › Maintenance, improper
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot/owner reported that he was flying at 140 mph when he encountered light turbulence, and the airplane started to shake. The shaking lasted for about three seconds before the pilot/owner could reduce power and pull back on the yoke to slow the airplane. He then continued on to his destination where he made a normal landing. After landing, extensive damage was found in the area of the aft fuselage. An investigation revealed the airplane did not have a current annual inspection. There were pinholes in the pitot tube where it had been welded. The airspeed indicator was tested, and it did not meet specifications. The ruddervators were examined for proper balance and rigging. The service balance range for the ruddervators is 16.8 to 19.8 inch-pounds trailing edge heavy (underbalance). Using the counterbalance method, the underbalance of the left and right ruddervators was determined to be 22.53 and 22.68 inch-pounds, respectively. Both the left and right ruddervator trim tab hinge pins had been installed incorrectly. The incorrectly installed trim tabs exhibited significant vertical free play near the inboard end; the tabs also had restricted up and down angular travel. The ruddervator balance and the trim tab installation had been performed by two different aircraft maintenance facilities.
Probable cause
improperly balanced ruddervators and improperly installed ruddervator (elevator) trim tabs, due to improper maintenance, which resulted in ruddervator flutter and substantial damage in the area of the aft fuselage. Factors relating to the accident were: improper planning/decision by the owner/operator (pilot) by failing to ensure that the annual inspection and required aircraft maintenance were performed; and turbulence that led to vibration of the improperly balanced ruddervator.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI96LA235
- Event ID
- 20001208X05946
- Case number
- CHI96LA235
- 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: local date, investigation status. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 1996-06-24.
- API snapshot SHA-256: efca1560c3226f4ab77df7dcf3eeb9a77a010dd09e06717875f64c741f57eff9; retrieved 2026-09-22T22:09:29.531Z.