CORROSION

Stress Corrosion Corrosion Fatigue Fretting Corrosion Heat Treatment

Preventive Maintenance

Much has been done to improve the corrosion resistance of aircraft, improvement in materials, surface treatments, insulation, and protective finishes. All of these have been aimed at reducing maintenance effort as well as improving relliability. In spite of these improvements, corrosion and its control is a very real problem

Forms of Corrosion

Type of Corrosion

Corrosion Control

Corrosion Removal

Preventive Maint.

that reqiures continuous preventive maintenance. Corrosion - preventive maintenance includes the following specific fuctions : An adequate cleaning. Thorough priodic lubrication. Detailed inspection for corrosion and failure of protective systems. Promt treatment of corrosion and tuch up of damaged paint areas. Keeping drainholes free of abstruction. Daily draining of fuel cell sumps. Daily wipe-down of exposed critical areas. Sealing of aircraft against water during foul weather and proper ventilation on warm, sunny days. Making maximum use of protective covers on parked aircraft. After any priod during which regular corrosion - preventive maintenance is interrupted, the amount of maintenance required to repair accumulated corrosion damage and bring the aircraft back up to standard will usually be quite high. Inspection. Inspection for corrosion is a continuing problem and should be handled on a daily basis. Overemphasizing a particular corrosion problem when it is discovered and than forgetting about corrosion until the next crisis is an unsafe, costly, and troublesome practice. Most scheduled maintenance checlists are complete enough to cover all parts of the aircraft or engine, and no part of the aircraft should go unchecked. Use these checklists as a general guide when an area is to be inspected for corrosion. Through experience it will be learned that most aircraft have trouble areas where corrosion will set in despite routine inspection and maintenance. In addition to routine maintenance inspections, amphibians or seaplanes should be checked daily and critical areas cleaned or treated, as necessary.