Final answer:
Aircraft corrosion in seawater and air is primarily caused by oxygen and salty conditions that accelerate the electrochemical process of rusting and corrosion. Protective measures include coatings and cathodic protection.
Step-by-step explanation:
The largest single cause of aircraft corrosion in seawater and in the air is due to oxygen and salty conditions. The presence of salt in seawater accelerates the corrosion process as the ions in salt water promote the formation of a salt bridge between the anodic and cathodic sites on the metal's surface.
When metals like iron are exposed to oxygen and water, they rust; this is a type of corrosion which is an electrochemical process that converts metals into more chemically stable forms such as oxides. Rust formation involves the creation of a galvanic cell, with oxygen reduction occurring at the cathode and iron oxidation at the anode, leading to the creation of iron ions that eventually form rust.
To mitigate corrosion, various methods can be employed such as covering the metal with paint, plastic, or other protective layers; using cathodic protection with more reactive metals like zinc or magnesium; or by creating metal alloys like stainless steel which are more resistant to corrosion.