Prompt Aircraft Corrosion Repair Saves Money Down The Road-y580

Overview Corrosion in a fuel system can cause an aircraft to be grounded until repairs can be carried out, resulting in a potential loss of revenue for the owner-operator. Fortunately, catching the corrosion early can minimize the time needed for repairs and aircraft down time. As a result, early aircraft corrosion detection and repair is a critical part of any aircraft maintenance program. Corrosion Causes By understanding the causes of corrosion, the most .mon reason for aircraft fuel leaks, you can improve your chances of performing aircraft corrosion repair before the costs are too high. Corrosion of metal aircraft parts is usually of two types; galvanic corrosion or chemical. Galvanic corrosion is seen at the interface of dissimilar metals, for instance steel and aluminum, in the presence of an electrolyte such as water, or seawater. When an electrolyte is present at such a junction, an electrical potential is set up between the two metals, causing one of the metals (the anode) to dissolve into the electrolyte and be deposited onto the other metal (the cathode), usually as a metal salt. Chemical corrosion is caused when a piece of metal is exposed to a chemical which causes an oxidation reaction. The most .mon form of this type of corrosion is rusted steel, caused by the iron .bining with oxygen from water or the air and forming iron oxide. While this is the most .mon example, this same type of corrosion can occur with almost any metal when it is in contact with a caustic or acidic fluid. Corrosion of non-metallic parts is primarily caused by exposure to acidic or caustic fluids or environments, but galvanic corrosion can also occur. Previously non-metallic corrosion has primarily been a cause of aircraft fuel leaks, but with increased use of carbon-fiber based materials in structural areas, this can now be a structural issue as well. Aircraft Corrosion Detection and Repair The best form of aircraft corrosion detection is frequent, periodic visual inspections. Metallic corrosion is usually evidenced by discoloration with by-products that can be gray, white, green or red. Care should be taken to inspect any areas where water or other fluids can accumulate. Areas requiring special attention include: "Battery .partments "Bilge areas "Areas in contact with the exhaust gases "Areas around cooling lines or vents "Recesses, such as those for wing flaps Once corrosion has been identified, it should be inspected closely to determine the penetration depth and a repair regimen decided on. Aircraft corrosion repair decisions should be based on the type of corrosion, the location and the depth to which it has penetrated. Repairing of surface corrosion may be a simple as a light sanding followed by reapplication of anti-corrosion coatings. Deeper penetration of the corrosion will have different remedies, up to the .plete replacement of the affected part, an extremely expensive and time intensive operation that may side-line the aircraft for weeks. Aircraft Fuel Leaks from Corrosion Fuel system corrosion is often the cause of aircraft fuel leaks and is discussed separately from structural corrosion for several reasons. First is that while the majority of the aircraft"s structure is metal of various types, the fuel system will often contain many polymer .ponents, causing the types of corrosion to be different. Second, significant sections of the fuel system are internal requiring different inspection techniques. Lastly structural corrosion is often caused by aircraft .ponents .ing into contact with liquids while the job of the fuel system is to contain many of those same fluids. While a full fuel system inspection need not be performed before every flight, it should still be carried out regularly. One check that can be done before every flight is the normal fuel tank sump check looking for water in the fuel tank. During this check, look not only for the presence of water, but also any discoloration of the fluid which may indicate the presence of microbes. Microbes are one of the areas where fuel system corrosion deviates from that of structural corrosion. Hydrocarbon-based fuels, especially when mixed with water from condensation or leakage, provide an excellent breeding medium for several strains of bacteria. These bacteria often form a film or a sludge which can actually eat into the materials of the aircraft"s fuel system. Such corrosion by these metal- and plastic-eating bacteria can be a significant cause of aircraft fuel leaks. These leaks, in return, can allow fuel to seep back along lines and into previously dry internal .partments. As the fuel collects in these areas, it can cause additional corrosion to both the aircraft"s fuel system and its structural .ponents. As a result, aircraft corrosion detection and repair should not be limited to the structural areas of the plane as it can occur anywhere. To ensure continued air-worthiness, it is important to ensure proper aircraft corrosion detection and repair regimen. A visual corrosion inspection should be performed on all external surfaces before each flight during the walk-around, in particular to look for aircraft fuel leaks. Furthermore, a detailed inspection of internal .partments and the fuel system should be made on a regular basis. Early detection will keep aircraft flying while minimizing aircraft corrosion repair costs and ensuring less down time. About the Author: 相关的主题文章: