Mark One Eyeball

Mark One Eyeball is a Colonial military term for visual reconnissance or flight plans improvised by the pilots themselves when searching for wreckage, survivors or managing other mission objectives. This becomes necessary when the use of technology isn't applicable or available due to unforeseen, unpredictable, or hazardous changes in completing a mission or task.

This term is actual British military slang for eyes or eye sight, derived from Britsh Royal Navy nomenclature for distinguishing sequential variations of a piece of equipment (i.e., "Mark 13 Depth Charge"). Since the human eye has not changed, it's called the Mark I Eyeball. The term's typically used when someone relies too much on their equipment: "Use your Mark One Eyeball!"

Commander Adama ordered such a search for Kara "Starbuck" Thrace (You Can't Go Home Again) when her ship was heavily damaged by an encounter with a Cylon Raider squadron (Act of Contrition).