Annex 6 refers to the operation of aircraft and provides guidance for pre-flight procedures, such as tanking of fuel, documentation, and weight and balance calculations. It also describes procedures for aircraft maintenance, which include inspections, maintenance of the aircraft systems, and emergency procedures. Additionally, it outlines emergency response plans that are needed in the event of an incident or accident. The guidelines described in Annex 6 are designed to maximize flight safety, minimize the chance of accidents, and help to promote a well-defined safety culture in the aviation industry.