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Other Factors Contributing to Mode S

During the late 1960's, several different factors combined to motivate the development of a new air traffic control technology.

Widespread Frustration

Problems with air traffic control started to become more obvious to passengers as flights became increasingly delayed. Among the travelers who noticed this problem was Herb Weiss, the head of the Radar Division at MIT Lincoln Laboratory at that time. Weiss had been working on a contract with the Air Force and often commuted to Washington, D.C. During one of his trips, he visited the FAA building and discussed the possibility of collaboration. In addition, he helped form an ad hoc committee at Lincoln Labs to to determine whether Lincoln could use its expertise to help solve the air traffic control problems.

Government Reorganization

Meanwhile, when President Johnson took office in late 1963, he commissioned several task forces to point out areas that needed special attention. Among the recommendations made by these task forces was the creation of a transportation department to organize all Federal transportation activities into one structure. At the time, no one expected anything to come of this recommendation, since similar ideas had been dropped in the past. However, Johnson proved his determination to carry it through when he announced his attention to create a new Department of Transportation in his 1966 State of the Union address.

Such a significant reorganization of government agencies required a great deal of planning and legislation to work out the exact details and division of responsibilities. After an organizational plan was drawn up, it was sent to Congress for approval. However, several members of Congress objected to portions of the plan, and a lengthy legislative battle ensued. It wasn't until April of 1967 that Congress finally approved the bill and the department was formed.

Among the changes made was the placement of the FAA under the control of the new Department of Transportation. The FAA was also renamed the Federal Aviation Administration. These changes represented a downgrading of the FAA's stature. Instead of reporting directly to the President, the FAA administrator now answered to the Secretary of Transportation. At this time, the Department of Transportation underwent a thorough assessment of its new responsibilities, including air traffic control. This assessment, combined with the impetus of the recent collisions and other problems, led to the formation of ATCAC in order to conduct an in-depth investigation of the situation.

The Vietnam War

At the same time, the ongoing war effort in the Vietnam War shifted emphasis and funding from military research to military applications. Because of the diminishing research budget, the Department of Defense encouraged its labs, including Lincoln, to demonstrate the usability and relevance of their work in non-military areas. Given Lincoln Labs' experience in radar, communications, and military air surveillance, civilian air traffic control seemed to be a feasible area to explore. To this end, an Ad Hoc Committee on Air Traffic Control was formed within Lincoln Labs. Their conclusion was that Lincoln could uniquely contribute to the field, and the Radar Division was subsequently restructured in 1970 into the Air Traffic Control Division.

The budget cuts due to the war extended to other government agencies as well, including the Department of Transportation. These budget cuts prevented the FAA from being able to upgrade to newly developed technologies and caused a shortage in air traffic controllers. The overall effect of this was that overworked controllers could not keep up with the increasing air traffic. The resulting delays and inefficiencies clearly indicated that at the rate of current traffic growth, the existing system was completely inadequate.

FAA Contract with Lincoln Labs

In order to realize ATCAC's vision of air traffic control, the FAA needed to find an organization which would be able to take the loose collection of requirements that ATCAC had proposed and turn them into a fully specified system, keeping in mind the requisite compatibility issue. Lincoln Laboratory, ultimately, became the ``technical arm'' for the FAA.

In 1971, the FAA signed its first contract with Lincoln Labs for a total of \$140,000 to explore the design of a new air traffic control technology. The project was entitled Discrete Address Beacon System (DABS), and the FAA emphasized compatibility as its primary concern in order to satisfy the needs of the aviation community. Lincoln's first task was to put together a technical development plan that would convince the FAA that the venture was technologically possible; to ``design a new beacon system that would not only be compatible with the old system, but could employ the same aircraft antennas and operate in the same frequency band.'' After the success of this six month planning project, the FAA contracted Lincoln Labs to develop and test DABS, later called Mode S.