Flight plans are documents filed by a pilot or flight dispatcher with the local Air Navigation Service Provider (e.g. the FAA in the United States) prior to departure which indicate the plane's planned route or flight path. Flight plan format is specified in ICAO Doc 4444. They generally include basic information such as departure and arrival points, estimated time en route, alternate airports in case of bad weather, type of flight (whether instrument flight rules [IFR] or visual flight rules [VFR]), the pilot's information, number of people on board, and information about the aircraft itself. In most countries, flight plans are required for flights under IFR, but may be optional for flying VFR unless crossing international borders. Flight plans are highly recommended, especially when flyi