Aviation Accident Summaries

Aviation Accident Summary FTW91LA064

CORPUS CHRISTI, TX, USA

Aircraft #1

N1195W

BELL 47G4

Analysis

A COMMERCIAL PILOT WAS MANEUVERING A HELICOPTER TO CONTROL A HERD OF CATTLE. THE PILOT NOTICED AN INTERMITTENT BINDING IN THE LEFT QUADRANT OF THE CYCLIC CONTROL. HE NOTIFIED HIS FLIGHT LEADER OF HIS INTENTIONS TO LAND AND INSPECT THE HYDRAULIC SERVOS IN THE FLIGHT CONTROL SYSTEM, AND INITIATED A PRECAUTIONARY LANDING CLOSE TO THEIR MAINTENANCE SUPPORT VEHICLE. DURING THE LANDING FLARE, THE HELICOPTER PITCHED SHARPLY TO THE RIGHT REAR AS THE LATERAL CYCLIC CONTROL BECAME LOCKED. THE PILOT APPLIED FULL RIGHT PEDAL TO TRY TO CUSHION THE LANDING AND PREVENT THE HELICOPTER FROM ROLLING. THE HELICOPTER WAS DESTROYED UPON IMPACT WITH THE MESQUITE TREES. THE FAILED LATERAL SERVO HAD BEEN REPLACED BY AN UNQUALIFIED PERSON PRIOR TO THIS FLIGHT.

Probable Cause and Findings

THE INITIAL RESTRICTED MOVEMENT AND EVENTUAL LOCKING OF THE CYCLIC CONTROL AS A RESULT OF THE FAILURE OF THE LATERAL SERVO. A FACTOR WAS THE INSTALLATION OF THE FAILED COMPONENT BY AN UNQUALIFIED PERSON.

 

Source: NTSB Aviation Accident Database

Get all the details on your iPhone or iPad with:

Aviation Accidents App

In-Depth Access to Aviation Accident Reports