Status of Instrument Landing Systems

During the past ten years a large number of instrument landing systems have undergone development and tests and a considerable fund of information has been accumulated concerning the shortcomings and advantages of each. The major airlines of the United States, the Federal Communications Commission, the Bureau of Air Commerce, and the Subcommittee on Instrument Landing Devices of the Radio Technical Committee for Aeronautics have reached an agreement as to the fundamental elements which should be incorporated in a practical instrument landing system and have also outlined a program of projected development. Having this agreement, it is now possible for all interested organizations to proceed with the perfection of a practical system by combining the superior features of the systems which have been tested and to carry on development which will further augment this system. At present, the major airlines are planning to install a number of instrument landing systems, having the fundamental elements agreed upon by the above-mentioned organizations, to be used on an experimental and pilot-training basis. It is recommended that the Bureau of Air Commerce. sponsor further development of instrument landing equipment until it meets the approval of all concerned with regard to operation, reliability, and ease of maintenance as well as fundamental elements. When this condition is reached, it is recommended that the Bureau of Air Commerce purchase, install, and operate a number of these instrument landing systems at various airports throughout the United States on an experimental basis.