The Fairchild Metro, a twin turbo-prop plane, is flown by more than 20 commuter airlines in the United States. It uses an 18 psig system that distributes regulated compressed air to the cockpit window purge and to the inflatable door seals. The air stream must be free of water to prevent window fogging or ice formation in the door seal system.
Fairchild, the aircraft manufacturer, selected the Beach Model GG filter with silica gel fill to remove water from the compressed air. It has performed successfully in thousands of flight hours.
The model GG filter is mounted in the center section of the wing. It is inspected periodically and replaced when the silica gel changes color from blue to pink, indicating saturation with water.
The low cost, disposable Model GG, rated at 5 scfm and 150 psig, is a highly-efficient desiccant type filter, ideally suited to instrument air, air to fluidic control devices and many other applications requiring a low volume of pure air.
The filter consists of a desiccant plus multiple fiber filtration pads, sealed in clear Lexan Polycarbonate body. The combination of filter media traps all contaminants — oil, mist, water and particulates as small as 0.5 microns.
— A variety of desiccant fills are available to meet specific needs
— Standard desiccant is provided for general use where hydrocarbons are present
— Silica gel fill may be used where moisture is the principal contaminant
— Calcium chloride, molecular sieve, activate carbon, or other special fils are available on request