When you inspect an aircraft or a particular area of an aircraft for corrosion, you should follow the steps listed below. Title aircraft materials, processes, cleaning and corrosion. Aircraft joints and corrosion control springerlink. Types of corrosion normally found on aircraft include. Polymers possess several properties that make them useful as aircraft materials, including low density 1. In a previous post, we discussed the basics of corrosion from the fundamental chemical reaction to the types of environments in which corrosion can occur. Surface corrosion an overview sciencedirect topics.
This advisory circular ac is a summary of the current available data regarding identification and treatment of corrosive attack on aircraft structures and engine materials. The following types of material are used in aircraft construction. The manufacturers instructions must be followed for. Corrosion control for aircraft ebook the faas advisory circular 43. Different types of steels pdfstainless steels, chemical. In both types of corrosion, the metal is converted into a metallic compound such as an oxide, hydroxide, or sulphate. Part of the reason was the slow development of strong, lightweight, metal aircraft structures and the lack of suitable corrosionresistant materials for allmetal aircraft. Faah808331a, aviation maintenance technician handbookairframe volume 2 pdf, 336. An aircraft crash in the netherlands was caused by disintegration of a jet engine. A knowledge of the basic stresses on aircraft structures will help you understand why aircraft are built the way they are. Most aircraft companies spend time on painting the aircraft to help delay corrosion, but inevitably, nature will prevail.
A complete set of manuals to perform aircraft cleaning and corrosion control functions consists of volume i corrosion theory, volume ii this volume, and volume iv consumable materials and equipment for aircraft and avionics. Guide to inspecting and preventing types of aircraft corrosion. Corrosion control part one types corrosion control part two forms corrosion control part three factors, maintenance, inspection corrosion control part four prone areas. Aircraft corrosion is an ongoing challenge for aircraft owners. The type and aggressiveness of the corrosion prevention and control program depend on the operational environment of the aircraft. The more an aircraft is exposed to seawater or salt air, the higher the risk of corrosion on the surface and throughout the different parts of the aircraft. Corrosion inspection frequency, corrosion identification, and especially corrosion treatment continues to be the responsibility of the operator. Corrosion control for aircraft ebook aircraft spruce. Corrosion and inspection of general aviation aircraft. Many aircraft structures are made of metal, and the most insidious form of damage to those structures is corrosion. Battery compartment, exhaust system and exhaust trails, wheel wells, lower area of the belly bilge, piano hinges, areas of dissimlar metal contact, welded areas, inside fuel tanks, metal fittings and. The appearance of corrosion varies withassociated with aircraft corrosion.
Pdf aircraft crash caused by stress corrosion cracking. Examples of exfoliation corrosion in the fin substructure of a usn p3 aircraft are shown in fig. Corrosion should always be removed by the mildest means available. The advisory circular is an extensive handbook, which deals with the sources of corrosion particular to aircraft structures, as well as steps the aircraft maintenance technician can take in the course of maintaining aircraft that have been attacked by corrosion. Aviation maintenance technician handbook general pdf, 64. Currently corrosion prevention and management in many civil and military fleets still relies strongly on the use of traditional find and fix maintenance practices, although this has been refined by the increasing use of corrosion prevention and control plans cpcp which provide a. The present focus on aging aircraft will lead to better corrosionresistant treatments for nextgeneration aircraft. The start of corrosion depends on how old the aircraft is, what type of environment it is placed in, and how often it is cleaned. Aircraft material an overview sciencedirect topics. Cleaning and corrosion control volume i corrosion program and corrosion theory 01 march 2005 this publication supersedes navair 011a509tm 1150034423, dated 1 may 2001 and navair 161540tm 1150034323to 11689, dated 1 sep 2000.
Firstly, the paper presents a brief overview of what corrosion is and what different types of corrosion are. Faa handbook on aircraft cleaning and corrosion control. These latter figures excluded maintenance overhead. Identify the areas of an aircraft that are most prone to corrosion. In the united states alone, aircraft corrosion is a multibillion dollar problem.
In aqueous environments, metals may be exposed to not only uniform corrosion, but also to various types of local corrosion including pitting, crevice, intergranular, stress, and galvanic corrosion. Types of corrosion i have seen corrosion in all its many forms and in my experience, galvanic and intergranular corrosion are the most insidious and dangerous types of aircraft corrosion. Aircraft cleaning and corrosion control flight mechanic. On some military aircraft types, corrosion maintenance hours are known to outstrip flight hours. The types of corrosion that occur on avionics equipment are similar to those found on airframe structures. Minimum aircraft separation is 3 m 10 ft on each side to facilitate maintenance stands. Corrosion is a natural process that converts a refined metal into a more chemicallystable form such as oxide, hydroxide, or sulfide. Corrosion control tips for aircraft technicians aviation. Fractography showed that the chain of events started with stress corrosion cracking scc of a pin attached to a. Currently, attention is being focussed on pitting and exfoliation corrosion in aluminium alloys and in highstrength steel. This is the most common type and is caused simply by exposing the metal to oxygen in the air, such as when paint is worn off wing skin or the fuselage. Control course outline, aviation mechanics 1 power.
Although these two types of corrosion are different, they do share one similarity. Some have a very small recoat time frame that must be considered when painting larger aircraft. Aviation, airplane, aircraft corrosion experts dvi aviation. Aircraft materials, processes, cleaning and corrosion. An aircraft is made of metal, and like any metal object, is highly prone to corrosion. Corrosion engineering is the field dedicated to controlling and preventing corrosion in the most common use of the word, this means. This type of damage can take place internally as well as on the surface. Some polymers are tough and transparent which makes them suitable for aircraft windows and canopies.
Corrosion testing many aircraft maintenance chemicals are used on components and structures that would be adversely affected by corrosion reference 1. This corrosion type occurs when two dissimilar metals make. Faa advisory circular ac 434a, corrosion control for aircraft. Performing organization names and addresses naval air systems command,47123 buse road, building 2272 suite 540,patuxent river,md,20670 8. Materials selection in wet areas, the design drainage schemes, the use of insulation standoffs, and sealing and finishing systems have all been improved.
Faah808331a, aviation maintenance technician handbookairframe volume 1 pdf, 193. The corrosion process always involves two simultaneous. From the moment the metal is manufactured, it must be protected from the deleterious effects of the environment that surrounds it. Also, a properly painted aircraft is easier to clean and maintain because the exposed surfaces are more resistant to corrosion. Institution dade county public schools, miami, fla. Both types of corrosion produce a reaction which turns the. Total immersion corrosion and sandwich corrosion are two test. As corrosion most often occurs in aqueous environments, we now explore the different types of degradation a metal can experience in. Corrosion damage in aircraft structure, if undetected andor left untreated, can undermine safety. The topcoat finish is applied to protect the exposed surfaces from corrosion and deterioration. While corrosion comes in many forms, the type that aircraft technicians are most interested in is both galvanic and concentrated cell a. When aluminumrich alloys of the dmalumin type were first used in aircraft construction, there occmred numerous instances of ex tremely rapid corrosion. Different types of steels pdfapplications, chemical composition, stainless steels, properties etcsteels are widely used materials in industry. Such stagnant microenvironments tend to occur in crevices process such as those formed under gaskets, washers, insulation material, fastener heads, surface deposits, disbonded scoating, threads, lap joints and clamps.
Due to the variety of materials used, environments and loads impacting the planes, a wide range of different types of corrosion may occur in aircraft structures. Corrosion control for aircrarft federal aviation administration. Drips, spills and leaks are common in vulnerable aircraft entryways, galleys, lavatories and cargo compartments. The carbon present in the form of ironcarbidefe3c increases the hardness and strength of the steel. They are the alloys of iron, carbon and other elements such as silicon, phosphorus, sulphur and manganese. The current approach in dealing with corrosion is to remove it as soon as it is found and either repair the corroded structure or. If left unchecked, corrosion can cause eventual structhis chapter provides an overview to the problems tural failure. Aircraft corrosion coatings in the aircraft industry. This type of corrosion is first seen as a general dulling of the surface and, if allowed to continue. Aircraft corrosion aircraft corrosion authorities are able of assessing corrosion failures containing stainless steels, copper, steel alloys and al alloys. Galvanic corrosion occurs when two different metals stainless steel and aluminum, for example come in direct contact with each other and an electrolyte of some type. Read this article to find out about the types of corrosion in aircraft and how to identify and prevent them.
Many classification can be used to categorize aircraft corrosion. Corrosion and inspection of general aviation aircraft civil aviation. These different types of corrosion are discussed in chapter 2 and in ac 434a, corrosion control for aircraft. In fact, many people are hesitant to purchase an aircraft that has been used in areas along the gulf coast or in the pacific coast region because of these planes have been exposed to such. The problem of skin corrosion is seen in many areas of the lockheed p3c maritime patrol aircraft and often results in multiple colocated repairs fig. Corrosion processes can have a significant effect on the integrity of structural materials and are usually associated with aircraft aging. Crevice corrosion is a localized form of corrosion usually associated with a stagnant solution on the microenvironmental level. Uniform corrosion this corrosion is also called general corrosion. This course gives maintenance technicians and engineers training in the control and prevention of aircraft corrosion. Corrosion removal before starting any corrosion removal, you must conduct an inspection and evaluation of the suspected area.
Chemtall, ardrox av30, corrosion prevention, penetrating, water displacing, corrosion inhibitor for aircraft aerosol price. The fuselage of an aircraft is subject the fives types of stresstorsion, bending, tension, shear, and compression. Metal corrosion is the deterioration of the metal by chemical or electrochemical attack. But, if you take the proper steps for aircraft corrosion prevention, youll be better equipped to stop it from developing in the first place. The primary difference between avionics and airframe corrosion is that a small. It is the gradual destruction of materials usually a metal by chemical andor electrochemical reaction with their environment. Loss of material due to corrosion in a component can contribute to fatigue problems as well as reduce strength capability.
686 669 1484 1296 1498 1470 941 601 1403 1069 1414 172 1469 262 433 390 1373 1471 934 824 149 1097 998 1499 190 1358 1170 545 281 30 147 145 1082 333 1124 87 436 861 1499 122