Aircraft Hydraulic Systems

3232 WordsAug 13, 201313 Pages
I. LANDING GEAR SAFETY DEVICES Most airplanes with a retractable landing gear have a gear warning horn that will sound when the airplane is configured for landing and the landing gear is not down and locked. Normally, the horn is linked to the throttle or flap position, and/or the airspeed indicator so that when the airplane is below a certain airspeed,configuration, or power setting with the gear retracted, the warning horn will sound. Accidental retraction of a landing gear may be prevented by such devices as mechanical downlocks, safety switches, and ground locks. Mechanical downlocks are built-in components of a gear retraction system and are operated automatically by the gear retraction system. To prevent accidental operation of the…show more content…
What happens is that atomic hydrogen found in such substances interacts chemically with the high tensile steel in the gear, causing the affected areas to transform chemically into a brittle alloy with a risk of fracturing. “The only way to counteract hydrogen embrittlement is to remove the affected component and bake it in a special oven at 375 F for 23 hours,” Lind tells AMT. “This allows the hydrogen atoms to migrate to the surface and then escape.” Maintenance best practices When damaged aircraft landing gear comes into the shop, it costs more to overhaul than landing gear that has been maintained properly. Here is what you can do to keep your landing gear costs down. The first step is lubrication. It may sound simple, but insufficient lubrication during regular usage causes unnecessary wear-and-tear in many of the system’s components. “Lubrication is critical to the movement of all articulated parts and joints of landing gear,” says Lind. “Proper lubrication ensures smooth functioning, less friction and wear, and the appropriate transfer of forces throughout the gear during use. Lubrication is key to keeping out water, de-icing fluid, and other corrosion-causing substances. Make no mistake; corrosion is a real problem for landing gear.” Before you lubricate, be sure to check the aircraft’s manual to find out what substances you can and cannot use. “In some cases, using the

More about Aircraft Hydraulic Systems

Open Document