Flying helicopters by computer.

Helicopter are notoriously difficult machines to control and even experienced pilots frequently have trouble negotiating simple maneuvers.If a measure of complexity is added, such as carrying a suspended weight or trying to hold a steady hover in windy conditions, the task becomes daunting.

Arthur Bryson of Standford University's Department of Aeronautical and Astonautics and his research team are trying to change all that. Using advanced control system and computer modelling concepts, they are perfecting a system in which helicopter pilots play the role of flight managers, instead of constantly having to worry about controlling the machine.

"We wanted to move the pilot's emphasis from controlling the helicopter to other tasks - like monitoring the meters and looking out the window more often to see if there's a risk of a midair collision," indicates Chris R. Purvis, a doctoral student on the research tea,. "Neglecting these |discretionary' tasks frequently causes accidents. The pilots is often too busy with the controls of pay much attention to the."

Helicopter pilots simultaneously have to manage the altitude, speed, and direction of the craft. This is especially difficult when approaching a hovering position and requires unusual coordination among the pilot's mind, hands, and feet. Acceleration in any direction is achieved by altering the angle of the rotor, which adjusts the direction of the rotor's thrust. To change the hover position, for example, the rotor must...