SAGE named an IEEE Milestone

MIT Lincoln Laboratory's role in developing SAGE is honored

On 27 June, the IEEE Boston Section presented MIT Lincoln Laboratory with an engraved plaque honoring the inclusion of the "Semi-Automatic Ground Environment" (SAGE) in the select list of IEEE Milestones. SAGE has been designated an IEEE Milestone because it revolutionized air defense and also contributed significantly to advances in the computer industry and air traffic control. The plaque that is to be installed permanently at the Laboratory reads: 

"SAGE-Semi-Automatic Ground Environment 1951-1958

In 1951 the Massachusetts Institute of Technology undertook the development of a continental air defense system for North America. The centerpiece of this defense system was a large digital computer originally developed at MIT. The MIT Lincoln Laboratory was formed to carry out the initial development of this system and the first of some 23 SAGE control centers was completed in 1958. SAGE was the forerunner of today’s digital computer networks."

IEEE leaders who joined in the presentations were Arthur Winston, Boston Section Milestones Committee Honorary Chair, and Gordon W. Day, IEEE President and CEO, who presented the SAGE plaque to Dr. Eric Evans, director of Lincoln Laboratory. SAGE is one of three new IEEE Milestones dedicated on 27 June. IEEE also honored Whirlwind, the first digital computer with a magnetic-core memory that could operate in real, interactive time, and Loran (long-range navigation), a system of navigation based on pulse-modulated synchronized signals.  Both Whirlwind and Loran will be commemorated by plaques installed at the Barta Building on MIT campus. The Whirlwind plaque was accepted by William Freeman of MIT, and the Loran plaque was accepted by Freeman and Captain Alan Arsenault, USCG.

Accepting Milestone Award for SAGEIEEE President Gordon Day (left) presents IEEE Milestone Award (shown on the far left) to MIT Lincoln Laboratory. Accepting the award is Dr. Eric Evans (right).

SAGE was the nation's first homeland air defense system and was the impetus for the establishment of Lincoln Laboratory. It was the first major real-time, computer-based command- and- control system. Designed to protect the United States from long-range bombers and other weapons, the SAGE system sent information from geographically dispersed radars over telephone lines and gathered it at a central location for processing by a newly designed, large-scale digital computer. As the system evolved, SAGE broke new ground in radar, communications, computer, information display, and computer programming technologies. SAGE not only revolutionized military command-and-controls, but led to landmark advances in online systems and interactive computing, real-time computing, and data communications using modems.

Engineered in response to a specific threat, SAGE was developed for the United States Air Force from 1950 to 1957 by the Massachusetts Institute of Technology's Digital Computer Laboratory, the Air Force Cambridge Research Laboratory, and MIT's Lincoln Laboratory. The work required scientific research in many different fields: computer hardware and software, radar, communications, and so on. The contract for manufacturing the AN/FSQ-7 computers was awarded to IBM. Western Electric Company provided buildings and internal power supply and communications. Phone lines were provided by the Bell System. System Development Corporation was responsible for the software which consisted of 500,000 lines of assembly language.

The uniqueness of SAGE is evident by the many innovations attributed to SAGE. In the areas of hardware and computer operations, SAGE's firsts included computer-driven displays, on-line terminals, time-sharing, high-reliability computations, digital signal processing, digital transmission over telephone lines, digital track-while-scan, digital simulation, core memories, computer networking, and duplex computers. SAGE integrated user interfaces such as interactive graphic displays, light-pen input, and on-line common database. SAGE also was the first system to offer high-reliability operations such as marginal checking, internal parity checking, and built-in test data reduction. In 1958, the job of integrating interceptor weapons into the SAGE software was massive enough to require creation of a new organization―MITRE―in order to continue systems engineering for SAGE.  Robert Everett, who was responsible for the SAGE system design and test, left the Laboratory to become MITRE's first director, assuring continued technical competence of the SAGE project.

Dedication Draws Digital Pioneers

Pioneers of SAGE, Jay Forrester and Bob Everett

The pioneers of SAGE, Dr. Jay Forrester (left) and Robert Everett (right), shared recollections of the development of SAGE and accepted the SAGE Milestone Award along with Dr. Evans.

Many of the people who collaborated in the SAGE achievements attended the presentation event, including Robert Everett, President Emeritus of MITRE, and Dr. Jay Forrester, MIT Professor Emeritus and patent holder for the magnetic core memory used in SAGE. Beginning in 1945, Forrester and Everett worked together at MIT to develop Whirlwind, the computer used in the SAGE air defense system. Both Forrester and Everett offered recollections of the SAGE Development as part of the ceremony dedicating the new IEEE Milestones.  Everett noted the SAGE program alone "trained hundreds of digital-system design engineers, thousands of computer programmers and thousands of digital-computer field engineers who gave great impetus to the new field of digital computers."

Background of the IEEE Global Milestones Program
The IEEE Global Milestones Program recognizes and honors significant achievements in electrical engineering, electronics, and computing. Established in 1983 in conjunction with the 1984 IEEE Centennial Celebration, the Milestones are a component of the IEEE's Global History Network (GHN), a wiki that is administered by the IEEE History Center and to which IEEE members and invited experts may contribute. The GHN's mission is "to be the world's premier site for the documentation, analysis and explanation of the history of electrical, electronic, and computer technologies, the scientists, engineers and business people who made these technologies happen, and on the history of the organizations to which these men and women belonged." Milestones, which may be unique products, seminal papers, patents, or decisive accomplishments, are nominated by an IEEE section, society, or chapter and are approved by the IEEE Board of Directors after recommendation by the IEEE History Committee. The Boston Section of the IEEE has been active in installing commemorative milestone plaques for viewing by the general public and visitors coming to New England.

The "SAGE (Semi-Automatic Ground Environment) 1951–1958" joins a prestigious catalog of 120 revolutionary technical achievements, ten of which are in the Greater Boston area, including the MIT Radiation Laboratory, the electric fire alarm system, the power system of Boston’s rapid transit, the first intelligible voice transmission over electric wire, the first wireless radio broadcast, and the Apollo Guidance Computer. The SAGE milestone is the second IEEE milestone awarded to Lincoln Laboratory. The first Lincoln Laboratory IEEE milestone is for First Real-Time Speech Communication on Packet Networks, 1974–1982. Each Milestone is commemorated with a bronze plaque that is placed at an appropriately meaningful site during a dedication ceremony.

Posted August 2012

top of page