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The Players

The three primary players in the development of the requirements and the technology of Mode S were Lincoln Labs, the technical arm, the AOPA, a strong voice from the user community, and the FAA, the government regulating arm. However, many other organizations also played a strong role in the shaping of the air traffic control systems of the 1960s. On this page, we provide you with some background information for some of these groups.



Lincoln Labs was originally established to deal with a different type of surveillance problem: detecting enemy military aircraft. The Department of Defense felt that a plausible scenario existed where Soviet bombers with nuclear weapons would ``fly over the north polar region at high latitude and then descend as it approached its target.'' Ground radar could be detected and avoided, making the aircraft virtually undetectable.

Over the years, Lincoln continued its efforts with surveillance technologies. In 1949 the Air Force contracted Lincoln to work on the ``Semi-Automatic Ground Environment'' (SAGE) system. This system used multiple radar sites to display all the aircraft within a designated area on the radar screen, making it possible for military controllers to vector air defense fighters toward invading enemy aircraft.

SAGE, a system of radar stations linked to a centralized digital computer, was essentially a predecessor to modern air traffic control systems. Because of these previous ventures, Lincoln Labs researchers had extensive knowledge of radar and communications. When the FAA finally decided to fund Lincoln Labs to design a new technology, the Air Traffic Group was officially formed. There were originally 5-6 members in the group, recruited from the other divisions at Lincoln, primarily the Radar and Communications Group.

Many of those involved with the initial development of Mode S had graduated from MIT with backgrounds in electrical engineering and communications design. Paul Drouilhet, for instance, had participated in the development and test of long-range, air-ground communications. Other members included Herb Weiss ('40), Edward Kelly ('45), Walter Wells ('52), George Colby ('53), Thomas Goblick ('58), Jerry Welch ('59), and Bill Harman ('68).

  • Air Traffic Control Group (#92) Pamphlet


    FAA

    The collision of two aircraft over the Grand Canyon in 1956 that killed 128 people raised awareness that the existing systems of aircraft separation were not appropriate for the increasingly crowded skies. The FAA was formed as the Federal Aviation Agency in 1958 with the passing of the Federal Aviation Act. Its purpose was to establish and run a broad air traffic control system to maintain safe separation of all commercial aircraft through all phases of flight. It was also given jurisdiction over all other safety-related matters for aviation.

    In reality, the FAA's control over aviation matters was not complete, since, as a government agency, they needed to balance the needs of the various politically active factions of the aviation community. Additionally, the FAA tended to rely on external advisors in technical matters. Therefore, when the ATCAC report indicated that a new air traffic control system was needed, the FAA looked for a suitable agency to carry out the task of designing such a system.


    AOPA

    The AOPA was founded in 1939 with the goals of making flying safer, more affordable and more fun. It's the largest civil aviation organization in the world, with 365,000 members; this includes more than half the pilots in the United States. The organization faced its first major challenge during World War II, when the government attempted to ban all civilian flying. The AOPA helped fend off this measure by establishing an identification program, but continued to be skeptical of future government regulation efforts.

    As air traffic control efforts increased, the AOPA fought to keep costs of mandatory equipment low, and increased in size and influence. AOPA also helped pilots by educating them about new navigation tools, and published several informative magazines designed for the general aviation community. More importantly, the AOPA legislative lobbying group became stronger and led general aviation in efforts to reduce costs and potential restrictions.

    The AOPA served an important role in representing the general aviation community and its interests. Their philosophy was best summarized by Max Karant, the founding editor of the AOPA Pilot and a prominent leader in the AOPA, ``Whatever ultimate system we come up with must serve all pilots who wish to use it.'' To this end, the AOPA consistently fought off ``efforts to price [private flying] out of the air with costly, unnecessary equipment requirements and more and more airspace regulations.'' The AOPA's influence was so strongly felt that even the development of new technologies was influenced by the general aviation community's desire to keep flying costs as low as possible.


    Professional Air Traffic Controllers Organization (PATCO)

    The Professional Air Traffic Controllers Organization (PATCO) is one of several air traffic controllers' organizations around the world. In their own words, "PATCO ... is an air traffic controller and weather observer's Union representing controllers and weather observers employed in the Federal Aviation Administration's Federal Contract Tower locations across the nation." PATCO was one of the most militant and vocal controller organizations, playing a large part in FAA-labor relations. They played a primary role in pushing the FAA to install new air traffic equipment and hire more controllers during the budget cuts of the 1960's. It was PATCO who ordered "Operation Air Safety", which declared that controllers should adhere to established separation standards, leading to the first of many "slowdowns" in air traffic. They also ordered the official "sickouts" that increased delay of air traffic either further. Membership in PATCO is restricted to controllers alone.




    Air Traffic Control Association (ATCA)

    The Air Traffic Control Association was established in 1956 by a group of air traffic controllers, and is "dedicated to progress in the science of air traffic control and the preservation of a safe flight environment." ATCA is not limited in membership to air traffic controllers, but instead also includes providers of air traffic control, system architects, manufacturers, suppliers, system operators, and users, anyone who "has an interest in promoting and encouragin the advancement of aviation and air traffic control." It represents the "broad spectrum of civil-military cooperation typical of global flying activities." The ATCA was another strong voice in expressing controller discontent and pushing for the improvement of the existing system in the 1960's.




    Air Line Pilots Association (ALPA)

    The Air Line Pilots Association was founded in 1931 and represents 59,000 airline pilots at 49 US and Canadian airlines. Its purpose is to "promote and champion all aspects of aviation safety throughout all segments of the aviation community; to represent, in both specific and general respects, the collective interests of all pilots in commercial aviation; ... to be a strong, forceful advocate of the airline piloting profession..." The ALPA represents the other significant portion of the piloting community from the AOPA. Though their concerns diverge at times, the ALPA and AOPA often combined forces in the 1960's to pressure the FAA to improve the technology and change their policies.




    Air Transport Association (ATA)

    The Air Transportation Association of America was founded in 1936 and is the only trade organizatoin for the principal US airlines. Its purpose is to "support and assist its members by promoting the air transport industry and the safety, cost effectiveness, and technological advancement of its operations; advocating commong industry positions before state and local governments; conducting designated industry-wide programs; and assuring governmental and public understanding of all aspects of air transport." The ATA has played an active and important role in aviation-related legislation, "including the creation of the Civil Aeronautics Board, the creation of the air traffic control system, and airline deregulation." The ATA, along with all the above agencies had a strong voice in criticizing the FAA's rate of progress in the 1960's.





  • The Story of Mode S: An Air Traffic Control Data Link Technology last modified: 12.06.2000