International air transport grew at double-digit rates from its earliest post-1945 days until the first oil crisis in 1973. The "scheduled" carrier activity is now more than 100 times what it was in 1945. Much of the impetus for this growth came from technical innovation through the introduction of turboprop aircraft in the early 1950s, transatlantic jets in the late 1950s, wide-bodied transports in the late 60s, airline deregulation in the mid-70s, and now fuel efficient twin jets with improved avionics and Extended-Range Twin-Engine Operations over water (ETOPS) certification. The industry is projected to continue its growth meeting increased loads with single (vice double) aisle aircraft due to passenger comfort and fuel economy demands. Paralleling the rise in international flights is the need for global weather information.
Standardized meteorological services are provided by all countries under the International Civil Aviation Organization (ICAO) in order to ensure safety of flight and a consistent level of service world-wide. As a contracting state of ICAO, the United States has agreed to provide flight documentation services to the international aviation community. Since October 1, 1998, in accordance with Chapter nine of Annex 3 to the Convention of International Civil Aviation, the Aviation Weather Center (AWC) has provided the required meteorological information to operators and flight crew members for: a) dispatch planning; b) flight crew pre-flight; and c) flight crews en route.
The AWC provides meteorological flight documentation at specified airports within the United States, its territories and possessions. The flight folder consists of the following, pertaining to the route of flight and approximate altitude: wind and temperature aloft forecast charts; significant weather charts (with abbreviated plain language descriptions of forecasts as appropriate); Terminal Aerodrome Forecasts (TAFs) for departure, destination and alternate; significant meteorological information (SIGMET) charts of tropical cyclones and/or volcanic ash as appropriate; and for flights of 2 hours or less, aerodrome reports (METAR), special reports (SPECI), SIGMETs (for any phenomena), and appropriate special air reports (AIREPs).