The Civil Airways and Their Radio Facilities

This paper describes the establishment of the radio facilities on the civil airways of the United States and their importance for air navigation. The legislation which created the Aeronautics Branch of the Department of Commerce and its organization is discussed. Description is given of the radiotelephone and radiotelegraph equipment used in the collection and broadcasting of weather information to aircraft. The transmitter used is rated at 2-kw output and is of the master-oscillator controlled type. A directive radio transmitting system using crossed coil antennas is employed to guide aircraft over the established airways. It is of such a type that the pilot receives one signal while within a narrow zone on the course, and other signals if off the course. This greatly facilitates flying under conditions of poor visibility. The regulations that have been proposed for the installation of radio equipment on aircraft are briefly given together with the more important frequencies allocated for aircraft work. The purpose and needs for these radio facilities and the way in which they have developed are also discussed.