Flying high

engineers could soon be able to produce all-electric aeroplanes with the help of a new device. The device called the Electro-Hydrostatic Actuator has been developed by engineers at the National Aeronautics and Space Administration ( nasa ) Dryden Flight Research Center, Edwards, usa . These planes would be safer and more fuel efficient than the existing aircrafts.

According to the researchers, the device eliminates or minimises airborne dependence on pneumatic, hydraulic and mechanical systems. The Electro-Hydrostatic Actuator and other electrical systems could also lead to 5-9 per cent fuel savings on an all-electric passenger plane, a 30-50 per cent reduction in the ground equipment, and reduction in the vulnerability of military aircraft in combat situations. The researchers tested the device on the left aileron of nasa 's F/A-18 Systems Research Aircraft without using the aircraft's central hydraulics.

Taking its signals from the aircraft's flight-control computers, the device uses its electronics to "fool" aircraft computers into thinking that a standard actuator is on board. The device contains a small amount of hydraulic fluid and uses an electric motor to drive its pump, creating a force that moves the aileron. Aileron is a movable airfoil used to control the balance of an aircraft in flight.

For many years, nasa , the us Air Force and the us Navy have sought to eliminate sophisticated but heavy hydraulic systems in aircraft in favour of electrical "power-by-wire" systems for operating flight controls. Besides savings in costs and support, electrical systems promise diminished vulnerability in combat by eliminating hydraulic lines in the fuselage and wing box.

The power-by-wire arrangement will also reduce complexity and improve reliability. The device is a part of the Electrically Powered Actuation Design Program. The us Air Force Research Laboratory manages the overall programme.

Air Transport Science & Technology