What's In A Window?

In 2014, the Centre for Process Innovation (CPI), a UK-based technology innovation center, released concepts for a windowless plane. The aircraft interior would be lined with video display panels that would show virtual views of the outside and interactive screens. Hypothetically, a windowless aircraft could reduce weight by eliminating the structures surrounding the window openings for strength, according to CPI.

The windows would be replaced with high-quality flexible organic light-emitting diode (OLED) technology, which is a thin, bendable and lightweight display screen that would bend with the fuselage and aircraft surfaces. Functional OLED technology is still in development, and CPI has worked on the back layer of the screen.  This concept will take about 10 years to be fully developed but it could be about two decades until it is released. 

Airbus filed a patent application in June 2014 for a partially digital image representation of the outside to replace a traditional window in the cockpit. According to the patent application, the “invention is also directed to increasing safety, in particular by improving the pilot’s perception and awareness of the outside scene forward of the aircraft [007]." 

The display may compromise a device with lasers to form a holographic image [0013], or be a digital image of the aircraft surroundings projected [0014]. Airbus has not responded to request for comment on the status of this patent application or project.

PPG Aerospace introduced redesigned sliding cockpit windows for the Airbus A320 family in 2015, which include a simplified clamp design for windows to allow the frame retainer and window panel to be installed as a complete assembly. The undamaged PPG frame retainers can be reused when the window panels need to be replaced. The cockpit windows have been redesigned to include stainless steel Z-retainer, proprietary PR-2060 polyurethane sealant as internal sealants to defend against moisture ingress and delamination.

Originally introduced in 2010, the sliding window includes similar technologies and materials used on the main windshields, and the price remains the same. PPG Aerospace delivered the first repaired aircraft to IndiGo in October. To date, there have been no reported age-related failures with the updated designs.

In October, Fokker Services, a business unit of GKN Aerospace, debuted the Electronically Dimmable Window System at MRO Europe in Amsterdam. The window transparency replaces the window shades and controls light, heat and noise that come through the aircraft. The technology was developed with Inspectech Aeroservice and Research Frontiers and is currently certified for single-aisle and widebody aircraft.

Typical installation includes wiring installed to provide power to control the dimming levels through the cabin management system and can be done over multiple overnights or integrated during a heavy check. Cost is structured by number of windows to be retrofitted and options available, including sensors to measure light intensity, mood-lighting systems and wider cabin upgrades to replace the interior panels in addition to the interior windows.

Nordam, an aerospace manufacturing and repair firm, has developed in recent months multiple coating technologies for passenger cabin and emergency door windows, including NORClear material, enhanced abrasion resistance and solar reflection. It also introduced a process to print various designs on passenger windows to enhance the passenger view.

For maintenance services, Nordam uses the “Diamond Mill” process to remove scratches and erosion from the window surface, adding up to 25-50% more life to the cabin window. Current customers for these services include Tier 1 suppliers, airlines and MROs like Airbus, Embraer and Rockwell Collins.

In September, Vision Systems created a business unit dedicated to embedded multimedia systems for Vision Systems has developed a Smart-Info Window to offer airlines a way to interact with passengers by displaying travel information, points of interest or stock exchange indices on a touchscreen. Additionally, specific advertising can be addressed to a particular passenger on the window and can buy products directly from the advertisement, or order snacks and drinks in flight.

At the National Business Aviation Association convention in November, Vision Systems announced its Acti-Vision Window for business aviation. The electronically dimmable windows include suspended particle device technology that changes the window from fully clear to a 99.9% light-blockage state instantly.