MIA04IA088 · Beech A36
Beech A36 · Incident: airframe, component or system failure en route
From Spruce Creek Airport (7FL6) to an unrecorded destination
Event
- NTSB case
- MIA04IA088
- 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
- Incident
- 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 A36
- Aircraft type
- Beechcraft 36
- 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
- N3670S
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Spruce Creek Airport (7FL6), Daytona Beach, FLTo 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
- 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
- None
Cause areas
- Other maintenance personnel › Maintenance, overhaul, improper
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The mechanic stated that he and the pilot were conducting a maintenance test flight, when the incident occurred. He further stated that after takeoff, and during climb to cruise, at an altitude of 1,000 feet AGL, as the pilot reduced power from 2,700 rpm to 2,500 rpm, all of a sudden there was a loud bang, and the airplane started to shudder and shake violently. He stated that the pilot reduced power, and returned for an otherwise uneventful landing. Examination of the airplane revealed that one blade of the three-bladed McCauley propeller appeared to be in negative pitch, and when moved, it revolved freely in the hub. Further examination revealed that the pitch change actuating pin for the No. 3 propeller blade had separated, with a threaded portion of the pin still remaining in the hub. On May 10, 2004, the incident McCauley propeller blade, and associated propeller parts, were examined at the NTSB Metallurgical Laboratory, Washington DC. The examination revealed that for the affected blade, the ferrule hole into which the fractured pitch change actuator pin had been inserted, had threads that did not extend into the hole as specified by the propeller manufacturer. The threads extended about one half the distance from the bottom of the hole, and fatigue cracking was found to be in the threads of the pin, and the fatigue crack had progressed about 95 percent of the way through the pin before it separated due to overstress. Records indicated that the propeller had last been overhauled on January 30, 1997,by a maintenance facility in Johnson City, New York, about 678 flight hours prior to the incident..
Probable cause
Improper maintenance/installation by the propeller overhaul/repair facility, which resulted in stress related fatigue and the eventual separation of the propeller pitch change pin.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record MIA04IA088
- Event ID
- 20040527X00681
- Case number
- MIA04IA088
- 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, damage. 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: b8128a451823692a1752976cf396021cf3bfb17921cf7c02a0bdf809ecf15397; retrieved 2026-09-22T07:34:28.216Z.