After developing its zonal drying technology to remove moisture from aircraft fuselages, Sweden's CTT Systems has expanded its offering to reintroduce humidity into the cabin for the health of passengers.
Ulf Liljenberg, CTT vice-president of sales and marketing, sees CAIR as a business and commercial aircraft product for long-haul operations.
Liljenberg says that an aircraft cabin will drop to as low as 5% humidity after only an hour of flying, causing a drying of the skin, eyes and mucus membrane, resulting in a decreased protection from viruses. He adds that the dehumidification is more pronounced on cabins with fewer passengers, like that of large business aircraft and premium airline cabins.
The CAIR system works with the zonal drying system to ensure that the humidity is captured, otherwise the added moisture plus the natural build-up in the crown of the fuselage could "rain in the plane", says Liljenberg.
By the end of 2009, the CAIR system was available as an supplemental type certification modification by Lufthansa Technik for large commercial business aircraft, such as the Boeing Business Jet, 767 and 747, as well as Airbus Corporate Jetliner, A330 and A340. CTT says that equipment for the system have the same part numbers to simplify interchangeability across types.
The CAIR system connects with the aircraft's potable fresh water supply, pulling cabin air through a filter pad sprayed with water, pushing the humidified aircraft out while being regulated by a cabin temperature sensor built into the system.
The system has been flight-tested on a 767 with Scandinavian Airlines for the past 18 months and was found to humidify the cabin, as well as desaturate insulation blankets previously saturated with an estimated 250kg (550lb) of water, leaving only 20-30kg of moisture, says Liljenberg.
Source: Flight International
