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LAX99LA004 · Burson REVOLUTION MINI 500 REVOLUTION

4 Oct 1998 · Moorpark, CA, United States

Burson REVOLUTION MINI 500 REVOLUTION · Accident: loss of control in flight while maneuvering

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Event

NTSB case
LAX99LA004
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

Burson REVOLUTION MINI 500 REVOLUTION

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
N418MB
Operator
Unknown
Onboard fatalities
Unknown
Route
From not recordedTo 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
Loss of control in flight
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

  • Pilot in command › Cyclic, improper use of
  • Pilot in command › Rotorcraft flight controls, improper use of

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

NTSB narrative

The helicopter did not return from an afternoon local area flight and the wreckage was located early the following morning. Both main rotor blades, the tail rotor assembly, the tail boom, and a section of the tail rotor drive shaft were found in a debris field approximately 1/8 mile from the fuselage wreckage. Both main rotor blades separated from the hub outboard of the root doubler and exhibited leading edge damage near the tip and downward bending. Additionally, the 'A' blade was bent smoothly aft approximately 30 degrees over its span. The tail boom was separated from the fuselage approximately 2 feet forward of the tail rotor gearbox. The separation exhibited a diagonal slicing appearance from upper forward to lower aft on the boom. The tail rotor drive shaft was separated at the same fuselage station as the tail boom, and the shaft had a dented appearance which resembled the leading edge radius of the main rotor blade. The main rotor mast exhibited a mast-bumping dent on one side of the mast at the hub attachment but no similar dent on the opposite side. Examination of the aircraft did not reveal any mechanical malfunction of the engine or flight control system.

Probable cause

The improper use of the cyclic flight control by the pilot, which resulted in low g flight load condition, which resulted in rotor disk divergence (mast bumping), and the main rotor blade striking and severing the tail boom.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record LAX99LA004
Event ID
20001211X11285
Case number
LAX99LA004
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: 98d3758a667ff0f23572594814fa851ec425a72ad94568c47e79273e97b0ea26; retrieved 2026-09-20T22:22:56.891Z.