Aircraft passengers will be able to block more light from coming through cabin windows with a new option for dimmable window shades by PPG Industries' aerospace transparencies group. The dual-panel version of ALTEOS(TM) Interactive Window Systems, which use Gentex Corp. electrochromic technology, shuts out more light than the standard systems to meet general-aviation interest.

PPG Aerospace is featuring the darker alternative for Alteos Interactive Window Systems at the National Business Aviation Association (NBAA) convention. An interactive demonstration in PPG Aerospace's exhibit at booth 4053 allows visitors to see the new version. The NBAA convention is Oct. 19-21 at the Georgia World Congress Center in Atlanta.

Alteos Interactive Window Systems allow passengers to control the amount of light coming through windows, switching from a bright, clear state to a dark state and intermediate levels. The standard systems use a single electrochromic panel installed between the inboard dust cover and outboard structural cabin window system.

"With two electrochromic panels, Alteos Interactive Window Systems reach a darker state, which general-aviation aircraft manufacturers told us they wanted," said Ryan Aspy, PPG Aerospace market development manager. "The standard systems and new version provide optical clarity and offer a broad dimming range."

Alteos Interactive Window Systems by PPG Aerospace are the world's first electrochromic window systems for commercial and business aircraft passenger cabins and the only certified systems being installed on new production aircraft, according to Aspy. They use Gentex electrochromic technology, which has been proven in nearly 150 million rearview mirrors over more than 20 years in the automotive industry. Alteos Interactive Window Systems are certified on the Beechcraft King Air 350i airplane, he said.

Alteos Interactive Window Systems replace pull-down, mechanical and other types of window shades for enhanced passenger comfort, interior aesthetics and aircraft operating efficiency, Aspy said. "Unlike older opaque shades, they enable passengers to maintain a view while dimming the window to reduce glare, and they can be darkened for sleeping or watching a movie," he said.

Electrochromics is the process of reversibly darkening specially prepared transparent materials through controlled application of an electric current.

The passenger-cabin windows in the PPG exhibit at the NBAA convention also have a solar-reflective coating that reduces solar transmittance by about half, compared with an uncoated stretched-acrylic cabin window, while maintaining high visible light transmittance, according to Aspy.

"We have transparency options available for airframe manufacturers that enable them to offer their customers innovative ways to make air travel more comfortable," Aspy said.