Fluid Line Identification Fluid lines in aircraft are often identified by markers made up of color codes, words, and geometric symbols. These markers identify each line’s function, content, and primary hazard. Figure 1 illustrates the various color codes and symbols used to designate the type of system and its contents. Fluid lines are marked, in … Read more
Tubing Materials CopperIn the early days of aviation, copper tubing was used extensively in aviation fluid applications. In modern aircraft, aluminum alloy, corrosion-resistant steel, or titanium tubing have generally replaced copper tubing. Aluminum Alloy Tubing Tubing made from 1100 H14 (1⁄2-hard) or 3003 H14 (1⁄2-hard) is used for general purpose lines of low or negligible … Read more
For the purpose of determining their overall condition, 14 CFR provides for the inspection of all civil aircraft at specific intervals, depending generally upon the type of operations that they are engaged in. The pilot in command (PIC) of a civil aircraft is responsible for determining whether that aircraft is in a condition for safe … Read more
When two dissimilar metals are placed in contact in the presence of moisture, galvanic corrosion can occur due to differences in their electrical potential. This condition is commonly referred to as dissimilar metal corrosion. The presence of an electrolyte, particularly salt water, accelerates the galvanic action. As a result, one of the metals undergoes oxidation … Read more
Hearing Protection The flight line is a place of dangerous activity. Technicians who perform maintenance on the flight line must constantly be aware of what is going on around them. The noise on a flight line comes from many places. Aircraft are only one source of noise. There are auxiliary power units (APUs), fuel trucks, … Read more
Eddy Current Inspection Eddy Current Inspection Electromagnetic analysis is a term describing the broad spectrum of electronic test methods involving the intersection of magnetic fields and circulatory currents. The most widely used technique is the eddy current. Eddy currents are composed of free electrons under the influence of an induced electromagnetic field that are made … Read more
The preceding information in this site provided general details regarding aircraft inspection. The remainder of this site deals with several methods often used on specific components or areas on an aircraft when carrying out the more specific inspections. They are referred to as nondestructive inspection (NDI) or nondestructive testing (NDT). The objective of NDI and … Read more
Keeping the shop, hangars, and flight line clean is essential to safety and efficient maintenance. The highest standards of orderly work arrangements and cleanliness must be observed during the maintenance of aircraft. Where continuous work shifts are established, the outgoing shift removes and properly stores personal tools, rollaway boxes, work stands, maintenance stands, hoses, electrical … Read more
When a technician gets involved with the weight and balance of an aircraft, it almost always involves a calculation of the aircraft’s empty weight and EWCG. Only on rare occasions are technicians involved in calculating adverse-loading CG checks, how much ballast is needed, or the loaded weight and balance of the aircraft. Calculating the empty … Read more
Preventive Maintenance Much has been done to improve the corrosion resistance of aircraft, such as improvements in materials, surface treatments, insulation, and modern protective finishes. All of these have been aimed at reducing the overall maintenance effort, as well as improving reliability. In spite of these improvements, corrosion and its control is a very real … Read more
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Aero Guide provides structured aviation study materials, technical explanations, and educational resources based on FAA handbooks and other aviation references. Explore aviation fundamentals, aircraft systems, airframe structures, powerplant systems, weight and balance, and more to support your aviation learning journey.
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