CHI00FA266 · Fairchild Hiller FH-1100
Fairchild Hiller FH-1100 · Accident: airframe, component or system failure en route
From Porter County Municipal Airport (VPZ) to Valparaiso, IN
Event
- NTSB case
- CHI00FA266
- 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
- 1 · 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
Fairchild Hiller FH-1100
- Aircraft type
- Fairchild Hiller FH-1100
- 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
- N250AD
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Porter County Municipal Airport (VPZ), Valparaiso, INTo Valparaiso, IN
- 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
- 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
- Destroyed
Cause areas
- Rotor drive system, main rotor mast(drive shaft) › Fractured
- Rotor system, main rotor › Separation
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
During cruise flight the main rotor mast fractured and the main rotor separated from the helicopter. Witnesses to the accident reported seeing the helicopter falling to the ground in multiple sections. The aft 7.5 feet of tailboom, including the tail rotor gearbox, was located 220 feet from the main wreckage. The main rotor hub and blades were located 146 feet from the main wreckage. The main rotor blades remained attached to the rotor hub assembly. The main rotor mast was fractured approximately 6 inches below the rotor hub assembly. The fracture was transverse to the longitudinal direction of the mast. The interior diameter of the main rotor mast was corroded and had several areas of surface pitting. According to the NTSB Materials Laboratory Factual Report, the main rotor mast contained a "flat" crack that contained crack arrest features indicative of fatigue cracking. The report states, "The crack arrest features in the flat fracture region emanated from corrosion pits on the inside diameter surface of the mast. The entire inside diameter surface had been affected by this corrosion in the area of the flat fracture region."
Probable cause
The in-flight fracture of the main rotor mast and the separation of the main rotor. Factors to the accident were the corroded main rotor mast that resulted in fatigue.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI00FA266
- Event ID
- 20001212X21660
- Case number
- CHI00FA266
- 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: 86482ebb4a51ef28beb8ab05c9d9f573bc42dabf5881b65921e2c7ca16b8ed5c; retrieved 2026-09-20T20:55:00.413Z.