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NYC92GA089 · McDonnell Douglas 500E

30 Apr 1992 · MOUNT ZION, KY, United States

U.S. Customs Service McDonnell Douglas 500E · Accident: airframe, component or system failure en route

From CVG · Cincinnati, OH to Cincinnati Northern Kentucky International Airport (CVG)

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Event

NTSB case
NYC92GA089
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

McDonnell Douglas 500E

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
N97BR
Onboard fatalities
Unknown
Route
From CVG · Cincinnati, OHTo Cincinnati Northern Kentucky International Airport (CVG)
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
Substantial

Cause areas

  • Rotor drive system, tail rotor gearbox(90 deg) › Separation
  • Rotor system, tail rotor blade abrasion strip › Disconnected

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

WHILE FLYING IN A CRUISE CONFIGURATION AT 1500 FEET MEAN SEA LEVEL, AND ABOUT 10 MINUTES INTO THE FLIGHT THE HELICOPTER STARTED TO VIBRATE. THE PILOT ELECTED TO MAKE A FORCED LANDING IN THE MOST SUITABLE AREA AVAILABLE. DURING THE DESCENT THE VIBRATION CONTINUED TO WORSEN. AT ABOUT 5 FEET ABOVE THE SELECTED LANDING SITE THE PILOT HEARD A LOUD BANG, THE HELICOPTER YAWED TO THE RIGHT AND PITCHED NOSE DOWN. THE PILOT LOWERED THE COLLECTIVE AND PUT THE HELICOPTER ON THE GROUND. METALLURGICAL EXAMINATION DETERMINED THAT THE LOSS OF THE ABRASION STRIP FROM THE LEADING EDGE OF TAIL ROTOR BLADE S/N 5086 INDUCED VIBRATIONAL STRESSES THAT WERE HIGH ENOUGH TO INITIATE FATIGUE FAILURE IN THE TAIL ROTOR GEAR BOX MOUNTING STUDS WHICH RESULTED IN THE SEPARATION OF THE GEAR BOX ASSEMBLY FROM THE HELICOPTER.

Probable cause

AN IN-FLIGHT SEPARATION OF THE TAIL ROTOR ASSEMBLY AS THE RESULT OF THE LOSS OF AN ABRASION STRIP FROM THE LEADING EDGE OF ONE OF THE TAIL ROTOR BLADES, WHICH INDUCED VIBRATIONAL STRESSES HIGH ENOUGH TO INITIATE FATIGUE FAILURE IN THE TAIL ROTOR GEAR BOX MOUNTING STUDS.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record NYC92GA089
Event ID
20001211X14498
Case number
NYC92GA089
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: d06660128f934daf4f7d80ccf4a72bc10fc60b0f4a015dbd486376c189450909; retrieved 2026-09-23T03:11:54.143Z.