|90-50D||ASR-520||Requirements for 760-Channel VHF Radio for Aeronautical Operations Encourages aircraft owners to upgrade their air-ground radio communication systems. Describes and upgrades civil air traffic control frequencies in the very high frequency (118.000 to 136.975 MHz) band. The 136.000 to 136.975 MHz band became available for aeronautical use on January 1, 1990.||04-09-1992|
|90-48C||AFS-820||Pilots' Role in Collision Avoidance Alerts all pilots to the potential hazards of midair collision and near midair collision, and to emphasize those basic problem areas related to the human causal factors where improvements in pilot education, operating practices, procedures, and improved scanning techniques are needed to reduce midair conflicts.||03-18-1983|
|90-42F||AFS-820||Traffic Advisory Practices at Airports without Operating Control Towers Contains good operating practices and procedures for use when approaching or departing airports without an operating control tower and airports that have control towers operating part time. Includes changes in radio frequencies and phraseology.||05-21-1990|
|90-34||AFS-840||Accidents Resulting from Wheelbarrowing in Tricycle Gear Equipped Aircraft Explains “wheel barrowing”, the circumstances under which it is likely to occur, and recommended corrective action.||02-27-1968|
Aircraft Wake Turbulence
This advisory circular (AC) presents basic information on wake vortex behavior, alerts pilots to the hazards of aircraft wake turbulence, and recommends operational procedures to avoid wake turbulence encounters.