MIA00TA070 · Bell UH-1H
Bell UH-1H · Accident: total loss of engine power (mechanical failure) while maneuvering
From X56 · Lehigh Acres, FL to an unrecorded destination
Event
- NTSB case
- MIA00TA070
- 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
Bell UH-1H
- Aircraft type
- Bell UH-1
- Category
- Helicopter
- 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
- N853M
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From X56 · Lehigh Acres, 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
- Maneuvering
- 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
- Total loss of engine power (mechanical 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
- Reason for occurrence undetermined
- Turbine assembly, turbine wheel › Fatigue
- Turbine assembly, turbine wheel › Fractured
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
According to the pilot, he was about 30 minutes into the post inspection maintenance flight at about 350 to 400 feet agl, when he heard a loud 'bang' and engine rpm decayed to zero. His choice of autorotation site required use of main rotor rpm to clear trees and he landed hard and rolled over. The T-53-L-13B engine underwent factory disassembly examination, with FAA oversight. Material analysis determined that portions of the 2nd stage GP turbine disc had fractured and separated due to peak strain low cycle fatigue, resulting in structural and imbalance damage and engine failure. No material, lubrication, or fuel control defects were identified that would have contributed to the disc separation.
Probable cause
A total loss of engine power due to turbine wheel fracture resulting from fatigue for undetermined reasons that resulted in an autorotation to unsuitable terrain and hard touchdown and rollover.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record MIA00TA070
- Event ID
- 20001212X20419
- Case number
- MIA00TA070
- 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: 83e731996e0f61f4bac849f4158a342619be48d40461452e30a7cc3da3bb13db; retrieved 2026-09-21T20:19:13.782Z.