NTSB Identification: LAX92LA038.
The docket is stored on NTSB microfiche number 45867.
Accident occurred Saturday, November 02, 1991 in SAN LUIS OBISPO, CA
Probable Cause Approval Date: 04/27/1993
Aircraft: QUESTAIRE VENTURE, registration: N71T
Injuries: 1 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

ON THE LANDING ROLL OUT, THE AIRCRAFT BEGAN A GRADUAL RIGHT TURN WHICH THE PILOT WAS UNABLE TO CORRECT DUE TO A FAILURE OF THE LEFT BRAKE AND NOSE WHEEL STEERING SYSTEMS. THE AIRCRAFT EXITED THE RIGHT SIDE OF THE RUNWAY AND THE NOSE GEAR FORK FAILED. THE AIRCRAFT NOSED OVER. THE AIRCRAFT WAS EXAMINED BY AN FAA AIRWORTHINESS INSPECTOR. THE INSPECTOR NOTED THAT THE HYDRAULIC BRAKE AND NOSE WHEEL STEERING SYSTEMS WERE INTERCONNECTED. THE 'O' RING SEALS IN THE BRAKE SYSTEM WERE FOUND TO BE BADLY DETERIORATED AND HE REPORTED THAT THE HYDRAULIC FLUID HAD LEAKED OUT. THE KIT MANUFACTURER RECOMMENDS USING AN AUTOMOTIVE TYPE FLUID IN THE SYSTEM. THE INSPECTOR STATED HIS OPINION THAT THE AUTOMOTIVE BRAKE FLUID WAS INCOMPATIBLE WITH THE 'O' RING MATERIAL.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

THE PILOT'S INABILITY TO CONTROL THE AIRCRAFT DURING THE LANDING ROLL DUE TO A FAILURE OF THE LEFT BRAKE AND NOSE WHEEL STEERING SYSTEMS. THE FAILURE OF THE BRAKE AND STEERING SYSTEMS WAS DUE TO A DETERIORATION OF THE 'O' RING SEALS CAUSED BY THE USE OF HYDRAULIC FLUID INCOMPATIBLE WITH THE RUBBER MATERIAL IN THE SEALS. A FACTOR IN THE ACCIDENT WAS THE INADEQUATE SYSTEM DESIGN BY THE KIT MANUFACTURER.

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