Weaning Your Baby Onto Solids. The term 'to wean' comes from an ancient phrase that means 'to accustom to'. So weaning refers to the period during which an infant gradually becomes accustomed to food other than milk (breast or formula). Up until 6 months of age, breast or formula milk alone is nutritionally adequate.
Occasional airplane vibration during flight is not unusual. There are many causes of airplane vibration, including landing gear extension and retraction, extension of speed brakes, free play in movable surfaces, and systems malfunctions.
Boeing designs airplanes to resist corrosion through selection of the proper materials and finishes and the use of drainage, sealants, and corrosion inhibitors. These designs are based on knowledge of what causes corrosion and the types of corrosion that occur in airplane structure. In addition, following a corrosion control program is necessary throughout the service life of the airplane.