Page:United States Statutes at Large Volume 55 Part 2.djvu/623

 55 STAT.] INTER-AMERICAN-RADIO COMMUNICATIONS-JAN. 26, 1940 1497 2.- that it might happen that frequencies allocated to routes by the 4stat. 1417 . General Radio Regulations of Cairo do not permit of insuring the necessary volume of traffic between fixed points, as well as all the essential communications with aircraft; 3.- that the aeronautical services are not prohibited by the General Radio Regulations to use frequencies in the bands allocated to the fixed services for communication between fixed points. it is recommended: a) that a rapid and effective radio communications service be estab- lished between control stations of the same lane, either between adjacent stations on the one hand, or between terminal sta- tions on the other. For this purpose, at least two series of frequencies will have to be provided according to the distances to be covered and for day and night operations; b) that long distance communications between control stations be strictly reduced to the exchange of messages relating to the security of aircraft and to the regularity of flights; c) that each government examine the possibility of providing for the use of fixed service aeronautical stations, suitable frequencies in the bands allocated to the fixed services, which will insure a rapid transmission of the traffic necessary to control stations with which a direct radio communication will be required. The frequencies found to be available as a result of this exami- nation will be placed at the disposal of all. It is expected that the contribution of each country of the frequencies will be proportionate in number to its interest in the service. d) that transmissions made by a special aeronautical station and intended for reception by one or more other such stations serving long trans-oceanic air routes and situated at distances appropriate to the propagation characteristics of the frequency band in use at a given time, shall be conducted on the same radio frequency. e) that frequencies allocated to routes or frequencies chosen for aeronautical fixed service should not be employed for meteor- ological messages which might be broadcast more economi- cally in general broadcasts or by other means; f) that to this end the countries participating in this Conference should prepare and exchange not later than March 1, 1941, pertinent data which may be of value. XI STUDY OF THE NEEDS OF THE AERONAUTICAL SERVICES FOR ADDI- TIONAL FREQUENCIES Considering: a) that the domestic and international aeronautical services have been marked by a steady growth and that they will undoubtedly continue to expand rapidly;

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