ABSTRACT
A commercial airplane is designed and operated for maximum yield, that is capacity to deliver as a function of operating and capital costs. Contrary to casual observations, corrosion of airframes is more severe on the inside than on the outside. Water causing corrosion on the inside of the fuselage structure is accumulated from vapour from human sources condensing against the cold fuselage skin where insulating materials can obstruct drainage. External damage is easier to detect and rectify than internal corrosion. Corrosion control was deemed to be too important to be conducted on an uncoordinated basis and a systematic industry-wide inspection programme based on a zonal system was imposed for all aircraft. The chapter also provides a discussion on gas turbine engines and its operation. The thermal and chemical environments within an engine depend on the functions of the various parts and on aircraft assignments, maneuvers and flight patterns.
