Electrically activated particles could darken or lighten the windows of the Boeing 7E7 if the technology is selected for the new passenger airliner.

US aerospace technology company Inspectech Aero Services is competing for the window contract by offering its four-year-old suspended particle device (SPD) technology. Its research aims to match the existing technology's capabilities with the airframe maker's requirements for 560 x 355mm (22 x 14in) windows.

SPD works by applying a current to particles in a glass sandwich structure. The current rotates the particles, which control the amount of light passing through the window.

"The ampage drawn will be quite minimal, per window. It's a very low current. It's only 22milliamps. That's not much even for something the size of the 7E7," says James Lang, president of Inspectech.

The SPD technology has been used before on business jets and helicopters but needs further work for the 7E7. Lang says substantial work has gone into ensuring the touch-sensitive switches are tough enough for the airline environment. SPD has been chosen by Lang's company over its own competing technologies such as liquid crystal switchable film because of the speed at which an SPD pane can lighten or darken.


Source: Flight International