What document is often required prior to starting a flight?

The requirement for a flight plan is crucial because it communicates crucial details of your flight to air traffic services. By filing a flight plan, you provide information about your intended route, estimated times of arrival, and the specifics of your aircraft, which helps enhance safety and coordination in the airspace.

While other documents like aircraft registration and pilot logbook serve important purposes, they are not necessarily required to be presented or filed before the flight. The aircraft registration verifies that the aircraft is legally recognized and registered. The pilot logbook keeps track of flight hours and experience but is not a prerequisite for flying. A passenger manifest, while useful for managing passengers and emergencies, is also not uniformly required for every flight.

Thus, the flight plan is specifically aimed at making sure that air traffic control is aware of your intentions, which is vital for maintaining safety and efficiency in the airspace.