LAX97LA245 · Classic Aircraft Corp. WACO YMF-5
Classic Aircraft Corp. WACO YMF-5 · Accident: propeller failure/malfunction en route
From Hilo International Airport (ITO) to an unrecorded destination
Narrative check · The NTSB narrative appears to contradict this record's flight rules. Values are shown as recorded, not corrected; compare with the narrative.
Event
- NTSB case
- LAX97LA245
- 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
Classic Aircraft Corp. WACO YMF-5
- Aircraft type
- Classic WACO YMF-5
- 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
- N553T
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Hilo International Airport (ITO), Hilo, HITo 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 91: General Aviation Possible conflict
- 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
- Propeller failure/malfunction
- 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
- Propeller system/accessories, prop blade retention › Separation
- Reason for occurrence undetermined
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
In cruise during a for-hire sightseeing flight over a volcanic crater the aircraft sustained an in-flight separation of the propeller. The pilot made a forced landing in a lava field. The pilot reported that there was no unusual vibration or other warning prior to the propeller separating from the aircraft. The pilot further reported that he personally inspected the propeller, retaining nut, and clevis pin the morning of the accident. Two prior flights were successfully completed and the accident occurred on the third flight of the day. During the aircraft recovery efforts, the propeller was found over a mile from the aircraft point of rest. Propeller hub/attachment components consisting of the forward cone, a snap ring, the hub retaining nut, and the clevis pin were not located. An examination of the aircraft was conducted by FAA Airworthiness inspectors who reported that nothing unusual was noted to the crankshaft splines, threaded front end (where the retaining nut is installed), or the grooves for the clevis pin. The examining inspectors stated that, 'apart from impact damage there was no other evident damage to propeller shaft that would suggest premature failure of propeller shaft that would cause departure of propeller from aircraft.'
Probable cause
Loss of the propeller retaining nut and associated hardware for undetermined reasons. A factor in the accident was the lack of suitable terrain for a forced landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record LAX97LA245
- Event ID
- 20001208X08431
- Case number
- LAX97LA245
- 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: bb24b3c7a89052ff5cc023ad53a23de30f4d21e52248aaeea1d86d16c0ae6c0a; retrieved 2026-09-21T21:19:59.575Z.