The importance of a properly functioning hydraulic system was dramatically demonstrated in Brooklyn, New York, one day in May 2004. A television news chopper -- a Eurocopter AStar -- was covering a shooting there when its hydraulic system suddenly failed.
The helicopter immediately descended, leveled briefly, rotated left until striking the roof parapet of a four-story building and then essentially disintegrated as it collapsed into a pile of rubble on the roof the building next door. All those aboard -- the pilot, pilot trainee and reporter -- suffered injuries but survived. Investigators traced the cause of the failure to a drive belt that had been installed inside-out and broke.