Foreign Object Debris
Foreign object debris or often known in the aviation industry as FOD is defined as a substance, debris or article alien to hardware or system which could potentially cause damage. The object may be foreign to an area or system and may be ingested by, or lodged in a mechanism. FOD objects are normally smaller items of debris; they are items that can be often over looked due to their obscure nature. A few examples of foreign object debris can be something as simple as a pen a fallen bolt a staple from a note book a pair of tweezers or even a small animal!
Foreign Object Damage
Foreign object damage (FOD) is defined as any damage attributed to a foreign object that can be expressed in physical or economic terms, which may or may not degrade the product’s required safety and/or performance characteristics. Some examples of how a foreign object causes damage include ingestion of loose hardware by an aircraft engine or passing debris through wind tunnel blades, short circuiting of flight electronics, contamination of sensors and optics, mechanisms that fail to operate properly and chemical attack on the physical properties of materials.