Corrosion Exam Questions With 100% Correct Answers 2023-2024, Exams of Advanced Education

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Corrosion Exam Questions With 100%

Correct Answers 2023-

Define corrosion - Correct Answer-The electrochemical deterioration of a material or its properties due to its chemical reaction with the surrounding environment. Why does corrosion occur? - Correct Answer-Because of the tendency of metals to return to their naturally occurring state; usually oxide or sulfide ores. The _______________ __________ Program reduces cost and improves safety. - Correct Answer-Corrosion Control Corrosion Technical Manual: Volume I - Contents - Correct Answer-Corrosion Program and Corrosion Theory - Program information, explains what corrosion is, why it occurs, forms it can take, and how to recognize it. Corrosion Control Technical Manuals: Volume II - Contents - Correct Answer-Aircraft - Cleaning and Corrosion control procedures for aircraft. Corrosion Control Technical Manuals: Volume III - Contents - Correct Answer-Avionics and Electronics - Cleaning and corrosion control procedures for avionics and electronics. Corrosion Control Technical Manuals: Volume IV - Contents - Correct Answer-*Most used volume for ATO rate. Consumable Materials and Equipment for Aircraft and Avionics - Lists approved materials and equipment for cleaning and corrosion control, and provides ordering information. Corrosion Control Technical Manuals: Volume V - Contents - Correct Answer- Consumable Materials and Equipment for Avionics - Lists approved Materials and equipment for cleaning and corrosion control, and provides ordering information, for avionics only. T or F: Volume V is for Marines ONLY - Correct Answer-FALSE. Volume V is for Air Force. NAVAIR 01-1A-509 is considered the "Corrosion _________", and takes precedence whenever there is a conflict. - Correct Answer-Bible Investigations have identified corrosion as a major factor in __________ failure in the field. - Correct Answer-electronics

• Correct Answer-

As much as ____% to ____% of military avionic failures are due to the corrosion process. - Correct Answer-30% to 40% Aircraft and avionic systems require the most stringent corrosion prevention and control programs when they are exposed to what types of environments? - Correct Answer- Salt-air and tropical environments. Who should be concerned with corrosion, cleaning, inspection, prevention, and treatment? - Correct Answer-Everyone (involved in maintenance, repair, and operation of aircraft and avionics systems). What is an electrolyte? - Correct Answer-Salt What are the 4 parts that make up the Preventative maintenance program at the Organizational/Unit and Intermediate Maintenance Activities? - Correct Answer-a. Reduce the maintenance time spent repairing corrosion damage. b. Improve reliability, durability, and service life. c. Make military avionics community aware of the extent of the problem. d. Report any deficiencies with materials and processes associated with corrosion control. In an electron, an electric current occurs when electrons are forced to move through __________ ______________. - Correct Answer-metal conductors. What are ions? - Correct Answer-Atoms or groups of atoms bound together which are either positively or negatively charged. T or F: Ions can move through metal conductors - Correct Answer-FALSE What are electrolytes? - Correct Answer-A liquid solution, usually water, containing ions. Is saltwater an electrolyte? - Correct Answer-YES. It is an aqueous solution of sodium ions and chloride ions. Theory of corrosion: All structural metals will corrode to some extent in a __________ environment. - Correct Answer-natural These four conditions must exist for corrosion to take place: - Correct Answer--A metal with a corrosive tendency is present. -This metal is known as the anode (anode=positive). -A dissimilar conductive material (cathode), has fewer tendencies to corrode than the anode. -A conductive liquid (electrolyte), must connect the anode and cathode (cathode=negative).

T or F: Most pure metals are not suitable for aircraft construction. - Correct Answer- TRUE Pure metals are used in combination with other metals, and sometimes non-metals, to form _________. - Correct Answer-alloys. Dissimilar Metals: When two dissimilar metals make electrical contact in the presence of an electrolyte, the rate at which corrosion occurs depends on what? - Correct Answer- The difference in their corrosive tendencies. The greater the difference in tendencies, the faster the corrosion occurs. The corrosion that takes place with two dissimilar metals (such as magnesium and gold in a humid atmosphere) is known as what type of corrosion? - Correct Answer-Galvanic corrosion Corrosion is accelerated by changes in what? - Correct Answer-temperature T or F: HIGH temperature environments cause accelerated chemical reactions. - Correct Answer-TRUE The best time to prevent corrosion is at the __________ stage. - Correct Answer-design Operations and Maintenance: What two types of aircraft have some airframe flexability?

• Correct Answer-Fixed-wing and rotary-wing. This causes seals to deteriorate and let in moisture and fluid. What types of aircraft systems are vulnerable to environmental conditions that cause corrosion, such as moisture and other fluids? - Correct Answer-ALL aircraft systems What is the greatest contributor to corrosion in avionic systems? - Correct Answer- Moisture What role do sand and dust on an aircraft surface play in corrosion? - Correct Answer- They can cause an abrasive action that can remove any protective coating and further expose the metal. Uniform Surface Corrosion: This is the most ___________ type of corrosion. - Correct Answer-common Uniform surface corrosion results from what? - Correct Answer-a direct chemical attack on a metal surface and involves only the metal surface. What is the chemical cause of Uniform surface corrosion? - Correct Answer-Occurs when oxygen, water, ozone, salt, and other materials chemically react with a metal surface.

Galvanic Corrosion: occurs when metals are in contact with each other and an _____________. - Correct Answer-electrolyte. Galvanic corrosion occurs when different metals which are known to be in electrical contact are well separated from each other on the ___________ __________ of metals chart. - Correct Answer-galvanic series What is pitting? - Correct Answer-Pitting is a common and severe form of corrosion that occurs on thin metal sheets such as printed circuit paths. Pitting is most commonly found on what two types of alloys? - Correct Answer- Aluminum and magnesium alloys. When does fretting corrosion occur? - Correct Answer-At all contact areas between materials under load subject to repeated vibration. What is hot corrosion? - Correct Answer-Corrosion in the absence of water that occurs at high temperatures, as as those found in turbine engine compressor and hot sections. What does corrosion look like? - Correct Answer-Appears as white, powdery, snow like mounds, and white spots on surface. T or F: Corrosion can be found on many different metal parts, including springs. - Correct Answer-TRUE Cleaning Aircraft Corrosion: Cleaning is _____ step in preventing aircraft corrosion. - Correct Answer-first Frequency of cleaning: Schedule: Navy aircraft must be cleaned at least every __ days when aboard ship and at least every __ days when ashore. - Correct Answer-7 and 14 When deployed within __ miles of salt water or when flown below ______ feet over salt water, daily cleaning or wipe down is required on all exposed, unpainted, surfaces, such as landing gear struts and actuating rods of hydraulic cylinders. - Correct Answer- miles, 3000 feet Immediate cleaning: takes place when areas are exposed to to what? - Correct Answer--Spilled electrolyte and corrosive deposit -Corrosive fire extinguishing materials -Salt deposits, relief tube waste or other contaminants -Salt water -Fungus -Chemical, biological or radiological (CBR) contaminants

Theoretical conditions and effects of corrosion is a topic that will introduce you to what?

• Correct Answer-The equipment available for general cleaning and the procedures for operating this equipment. WARNING: Do not service the Portable 15-gallon or 45-gallon Foam Generating Cleaning Unit without doing what first? - Correct Answer-Releasing pressure. Air Drying Oven: The circulating air drying oven dries avionic equipment and components using _____________ _____ and _____________. - Correct Answer- circulating air and temperature. Procedures for cleaning vary based on what two variables? - Correct Answer-Weather conditions and temperature ranges. Ex: when outdoor temp is high (80+ degrees) and when shade is not available, cleaning operations should be scheduled for early morning and late afternoon or night. Why should an aircraft be electronically grounded during cleaning operations and when moored or parked? - Correct Answer-In order to guard against the danger of static electricity. T or F: Before cleaning electrical and avionics equipment, make sure power is connected. - Correct Answer-FALSE. Power must be disconnected, lest injury or death result. NOTE: Selection Basis - Always use the _____________ form of cleaning that will accomplish the task. - Correct Answer-mildest form Cleaning selection is based on what 3 variables? - Correct Answer--Accessibility to the contaminant or corrosion -Type and extent of contamination or corrosion -Types of avionic equipment Accessibility: What type of inspection usually indicates the extent of contamination and corrosion damage? - Correct Answer-Visual Cleaning Restrictions: Who makes the selection of the cleaning track? - Correct Answer-The avionic cleaning facility supervisor. Air Drying: recommended for what? - Correct Answer-Housings, covers, and some hardware. What should Air drying NOT be used on? - Correct Answer-Should not be used for equipment containing cavities or moisture traps. Solvent Vapor Drying: Is the __________ and most _____________ means of drying. - Correct Answer-fast, efficient

This method uses the Solvent Ultrasonic Cleaner to dry by means of evaporation. Drying time is usually 15 seconds to 3 minutes. Conventional Lubricant Application Method: Lubricants should be applied ____________. - Correct Answer-sparingly. This prevents accumulation of dust, dirt, and other foreign matter. It's also important to wipe away excess lubricant. 3 ways to apply lubricants - Correct Answer--Grease guns: lever or pressure type ***-Oil, squirt and aerosol spray cans -Hand or brush Fasteners: are fasteners and the surrounding areas prone to corrosion? - Correct Answer-YES. There are thousands of fasteners on aircraft exterior surfaces, and these areas are common corrosion prone trouble spots. Human Waste: T or F: Human waste products are not corrosive. - Correct Answer- FALSE. They are very corrosive. Water Entrapment: T or F: these drains are very effective against corrosion. - Correct Answer-FALSE. These drains are ineffective, either because of improper location or because they are plugged by sealants, fasteners, dirt, grease, or debris. Magnesium Parts: are extremely prone to _____________. - Correct Answer-corrosion. The most useful tool for detection of corrosion is the __________ ______. - Correct Answer-human eye. What are the keys to successful preventative maintenance of corrosion? - Correct Answer-Frequent inspections and spot checks. Intrusive Sources: _________ and _______ __________ in the bilge area also direct moisture through the aircraft to equipment in areas that are assumed to be protected. - Correct Answer-Cables and wire bundles Differences between Avionics and Airframe Corrosion: (8 points) - Correct Answer-1. Very small amounts of corrosion can cause severe damage.

2. Dissimilar metals are often in electrical contact.
3. Stray electrical currents can cause corrosion (ionization).
4. Active and dissimilar metals in contact are often unprotected. *5. Closed boxes can produce condensation.
5. Hidden corrosion is difficult to detect.
6. Many materials are subject to attack by bacteria and fungi.
7. Organic materials can produce corrosive vapor. Early detection, identification, and treatment, can minimize the _________ and _______ of corrosion. - Correct Answer-damage and cost

___________ inspections are the most widely used method for the detection and evaluation of corrosion. - Correct Answer-Visual Use the following 3 categories in reporting the degrees of corrosion: - Correct Answer- Light, Moderate, and Severe Light Corrosion: Protective coating is scarred or etched and the condition of the metal is characterized by discoloration and pitting to a depth of approximately how thick? - Correct Answer-one mil (0.001 inch) maximum. Moderate Corrosion: This looks like corrosion except that there may be some blisters or evidence of scaling and flaking of coating or paint system, and the pitting depths may be as deep as... - Correct Answer-10 mils (0.010 inch). Severe Corrosion: Appearance may be similar to Moderate Corrosion with severe intergranular corrosion, blistering exfoliation, scaling, or flaking. The pitting depths are deeper than... - Correct Answer-10 mils (0.010 inch).

• This damage must be removed by extensive mechanical sanding or grinding. WARNING: Abrasive blasting operations create airborne particles which may be hazardous to the ______ and _______. - Correct Answer-skin and eyes. A hood, gloves with gauntlets, and adequate ventilation are required. WARNING: All powered corrosion removal procedures create ___________ ____________. - Correct Answer-Airborne particles. Adequate ventilation, respiratory protection, and eye protection are required. WARNING: Chemical prepaint treatments are toxic and require the use of what? - Correct Answer-Rubber gloves and chemical- or splash proof -goggles. If the material (acid) accidentally comes in contact with skin or eyes, flush immediately with clean water. WARNING: Mixing and application should be done in what kind of area? - Correct Answer-An adequately ventilated area. Avoid prolonged breathing of vapors. Chemical film materials are strongly oxidizing and are a fire hazard in contact with combustible and readily oxidizable materials and must be stored separately. WARNING: What should you do with rags contaminated with chemical film materials? - Correct Answer-Thoroughly rinse and dispose of as soon as practicable. Do not use chemical prepaint treatment on high-strength steel. Catastrophic failure may occur due to hydrogen embrittlement. CAUTION: Do not allow _____________ ___________ _______________ to enter faying surface areas or other areas where the solutions cannot be adequately removed by rinsing. - Correct Answer-chemical prepaint treatments

Do not store chemicals or prepaint treatments in steel, lead, copper, or glass containers. Use only plastic, rubber, or stainless steel. What is the purpose of sealants? - Correct Answer-To prevent the intrusion of moisture, rain, salt water, dust, and aircraft fluids. ___________ are one of the most important tools for corrosion prevention and control. - Correct Answer-Sealants 9 Step Application of Sealants - Correct Answer-1. Fuel Sealing (Fuel tanks)

2. Pressure Area Sealing (cabin areas)
3. Weather Sealing (exterior skin surfaces)
4. Firewall Sealing (engine and ordnance areas)
5. Electrical Sealing (bulkhead wiring, electrical connectors and components)
6. Acid-resistant sealing (battery compartments, relief tanks)
7. Window Sealing (windows)
8. High temperature Sealing (engine areas, anti-icing ducts, some electronics)
9. Aerodynamic Sealing (exterior skin surfaces) Sealants: Warning and Cautions: T or F: Sealants can be dangerous if application procedures are not followed. - Correct Answer-TRUE. 4 tools for applying sealants - Correct Answer-1. Brush
10. Spatula
11. Caulking Gun
12. Masking Tape Damaged Sealants: When and where are the aircrafts sealed? - Correct Answer-At the factory or by the Depots during rework. T or F: When a previously applied sealant is damaged, it is up to the technician and a visual inspection to determine if a new sealant is required. - Correct Answer-FALSE. It is MANDATORY to apply a fresh sealant whenever the previously applied sealant is damaged. Sealant Shelf Life: How can you determine the shelf life of a sealant? - Correct Answer- The date of the manufacture and the shelf life are listed on each container. The shelf life of a sealant is dependent on storing the sealant in its __________, ____________ container in an area where the temperature does not exceed ___ degrees Fahrenheit. - Correct Answer-original, unopened 80 When do you check a sealant container to determine if the material has exceeded its shelf life? - Correct Answer-Prior to use.

If a sealant has exceeded its shelf life, it shall not be used until __________ _____________ has been performed. - Correct Answer-update testing Paint Systems: Purpose: What is the primary objective of any paint system? - Correct Answer-To protect all exposed surfaces against corrosion and any other forms of deterioration. 5 Operational uses of Paint Systems - Correct Answer-1. Glare reduction by flat coatings

2. Special finishes for reduction of heat absorption
3. Camouflage and other detection countermeasures
4. High visibility requirements.
5. Identification markings What are the 4 ways to apply paint coatings? - Correct Answer-1. Brushes
6. Touch-up pens
7. Rollers
8. Spray guns The EPA has established specific requirements for paint spray equipment used on aircraft surfaces. What is the EPA? - Correct Answer-Environmental Protection Agency Why are brushes and rollers the environmentally preferred form of touch-up painting? - Correct Answer-They produce little paint waste and do not require solvent clean up. T or F: Natural and synthetic rubber can be painted and/or oiled when necessary. - Correct Answer-FALSE. Grease should not be applied to rubber parts, but some parts, such as "O" rings, require a grease coating. What should you do when fungus is noted on rubber parts? - Correct Answer-Clean the parts and remove the fungus in accordance with NAVAIR 01-1A-509. WARNING: Depleted uranium is _____________ _________ and shall be worked only under a license from the Nuclear Regulatory Commission. - Correct Answer-extremely toxic No drilling, sanding, or other mechanical work is permitted on depleted uranium by any service maintenance activities. WARNING: If the protective finish (plating) which covers the depleted uranium is chipped, peeled, or otherwise removed, then what must you do? - Correct Answer-The part must be returned to the licensee for rework or disposal. Hardware Repair: What types of aircraft electrical and electronic units must be opened up and inspected for evidence of internal moisture and corrosion? - Correct Answer-All of them!

What are the 3 general equipment areas that are commonly affected by corrosion? - Correct Answer-Bilge Areas, Equipment Bays, and Engine Compartments (B double E) Avionic equipment bays and installed equipment are highly susceptible to corrosion. This is especially true for ________________ and ___________ using external ram air- cooling. - Correct Answer-helicopters and aircraft Whenever working in the avionics equipment bays, technicians should routinely survey what area? - Correct Answer-The inside of the equipment bays. Engine Compartment: The engine compartment, hardware, electrical connectors, terminal boards, junction boxes, and ram air turbine should be inspected for ______ _______ contamination and _______________. - Correct Answer-salt spray, corrosion. Battery Compartment: The battery, battery cover, battery box and adjacent areas (especially below battery compartment) are subject to the corrosive action of what? - Correct Answer-Electrolytes WARNING: The inhalation of carbon composite fibers resulting from aircraft fires and/or aircraft material damage may be harmful to personnel. What must you wear when handling these materials? - Correct Answer-A full face piece respirator, and close- weave cotton gloves. CAUTION: Aircraft construction utilizing carbon/epoxy fiber composite materials and metal structure or substructure creates high potential for what? - Correct Answer- Galvanic corrosion cells WARNING: The _________ _________ of composite materials may be released into the atmosphere if the epoxy binder burns. - Correct Answer-carbon fibers This occurs at temperatures in excess of 600 degrees Fahrenheit. *In addition, fibers may be released by an explosion or high impact crash. WARNING: Do not put power to or start up an aircraft or electronic/electrical equipment that has been exposed to debris until what has been done? - Correct Answer- Decontamination by vacuuming and/or washing is completed. Failure to observe these procedures may result in electrical short circuits and fires. NOTE: It is recommended that industrial hygiene/safety personnel be contacted to provide what during cleanup? - Correct Answer-Specific information regarding hazards to personnel. WARNING: ______________ _____ used for drying can create airborne particles that may enter the eyes. - Correct Answer-Compressed air Pressure shall not exceed 10 psi. Eye protection is required. What does PKP stand for? - Correct Answer-Purple K Powder

When combined with water, PKP could corrode or stain surfaces, and should be removed from all surfaces as soon as possible. What does AFFF stand for? - Correct Answer-Aqueous Film-Forming Foam AFFF mixed with water does not usually cause corrosion. What is the primary concern in removing volcanic ash? - Correct Answer-The extreme abrasiveness of the ash.