CHI04LA046 · Beech 95-B55
Beech 95-B55 · Accident: airframe, component or system failure on approach
From South St Paul Municipal Airport/Richard E Fleming Field (SGS) to Saint Paul Downtown Holman Field (STP)
Event
- NTSB case
- CHI04LA046
- 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
- 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
- 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 95-B55
- Aircraft type
- Beechcraft 55
- 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
- N221Q
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From South St Paul Municipal Airport/Richard E Fleming Field (SGS), South St. Paul, MNTo Saint Paul Downtown Holman Field (STP), St. Paul, MN
- 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
- Approach · VFR pattern downwind
- 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
- Landing gear, normal retraction/extension assembly › Failure
- Pilot in command(cfi) › Gear extension, not possible
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The airplane sustained substantial damage while landing wheels-up, subsequent to the crew being unable to extend the landing gear. The certified flight instructor (CFI) stated the landing gear did not fully extend and the gear-down lighting did not illuminate while on downwind. The CFI reported they attempted to retract the landing gear, but the gear-up light did not illuminate. The CFI stated they attempted to extend the landing gear again; however, the cabin began to fill with smoke, and the gear motor and right generator circuit breakers both tripped. The CFI reported they performed the manual gear extension procedure without success. The CFI stated that "The manual gear extension handle was not catching anything and turning very loosely." The CFI reported they landed with the landing gear retracted and subsequently impacted a runway sign. Subsequent to the accident the landing gear extension/retraction system was examined while the airplane was elevated on jackstands. The landing gear did not extend using the electric or the manual gear extension procedure. The landing gear extension/retraction gearbox was disassembled for further inspection. One of the actuator worm gear bearings was found in several pieces, resulting in the worm gear being lodged between the sector gear and the gearbox housing. According to the Beech 95-B55 maintenance manual, the landing gear extension/retraction gearbox is to be replaced or overhauled every 2,000 hours. The accident airplane's gearbox assembly had accumulated 2,137 hours since the last overhaul and 6,342 hours since new.
Probable cause
The failure of the worm drive bearing that resulted in the failure of the landing gear extension/retraction gearbox, which ultimately resulted in the extension of the landing gear not being possible. A factor to the accident was the airport sign that the airplane impacted during the wheels-up landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI04LA046
- Event ID
- 20040102X00005
- Case number
- CHI04LA046
- 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, coordinates. 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: 9642caeff959fbb5d07549872222f6f2a609ad9de06078d8957b16980bc51450; retrieved 2026-09-22T08:03:38.523Z.