Plain English Meaning

A careful check of the aircraft before flying it to make sure everything is in good working order and legal to fly. The pilot looks over paperwork, the airframe, the engine, fuel, oil, and key systems before getting in to start up.

Full Definition

A systematic evaluation conducted before flight to determine whether the aircraft is in a safe and airworthy condition for the intended operation. It includes reviewing required documents, checking maintenance status, and performing a thorough visual and functional inspection of the aircraft and its systems in accordance with the manufacturer's checklist.