FTW91FA158 · Beech K35
Beech K35 · Accident: loss of engine power en route
From Springfield Branson National Airport (SGF) to Sundance Airpark (HSD)
Event
- NTSB case
- FTW91FA158
- 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 K35
- 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
- N817R
- Operator
- Hershel Maurer
- Onboard fatalities
- Unknown
- Route
- From Springfield Branson National Airport (SGF), Springfield, MOTo Sundance Airpark (HSD), SUNDANCE, OK
- 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
- Loss of engine power
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Wire, static
- 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
- Engine assembly, bearing › Failure, total
- Engine assembly, connecting rod bolt › Failure, total
- Other maintenance personnel › Maintenance, overhaul, major, not performed
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
DURING ROUTINE MAINTENANCE, THE ENGINE WAS RUN UP TO FULL POWER WITH THE AIRPLANE TOW BAR ATTACHED. AS THE NOSE STRUT COMPRESSED, THE PROPELLER STRUCK THE TOW BAR. A SERVICE BULLETIN ADDRESSES THIS ISSUE STATING THAT THE ENGINE SHOULD BE DISASSEMBLED AND INSPECTED FOR DAMAGE. THE MAINTENANCE FACILITY DID NOT ADVISE THE OWNER OF THE EXTENT OF THE DAMAGE INCURRED. AS A RESULT OF THE PROPELLER STRIKE, THE CRANKSHAFT MAIN BEARINGS ROTATED IN THE SADDLES, FAILING MECHANICALLY. THIS RESULTED IN THE BLOCKAGE OF OIL PASSAGES AND THE SUBSEQUENT FAILURE OF THE NUMBER TWO CYLINDER CONNECTING ROD CAP BOLTS. TOTAL ENGINE FAILURE RESULTED. SUITABLE TERRAIN FOR THE FORCED LANDING WAS NOT AVAILABLE. IMPACT OCCURRED IN SOFT CULTIVATED TERRAIN.
Probable cause
TOTAL POWER LOSS DUE TO FAILURE OF THE CRANKSHAFT BEARINGS AND CONNECTING ROD CAP BOLTS RESULTING FROM THE MAINTENANCE FACILITIES' FAILURE TO OVERHAUL THE ENGINE. A FACTOR WAS THE LACK OF SUITABLE TERRAIN FOR THE FORCED LANDING.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record FTW91FA158
- Event ID
- 20001212X17862
- Case number
- FTW91FA158
- 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: a5cf15a0329921188e4c1c0279036919de67d4abeae2bb333d24fb248c65ad0b; retrieved 2026-09-21T15:21:43.302Z.