From Whirlwind to MITRE: The R&D Story of the SAGE Air Defense Computer (review)

From Whirlwind to MITRE: The R&D Story of the SAGE Air Defense Computer. By Kent C. Redmond and Thomas M. Smith. Cambridge, Mass.: MIT Press, 2000. Pp. vii+535. $49.95.

In 1980, Kent C. Redmond and Thomas M. Smith published their classic Project Whirlwind: The History of a Pioneer Computer, which remains the most important account of the first digital electronic computer, developed at the Massachusetts Institute of Technology during the late 1940s and early 1950s. The idea for the SAGE (Semi-Automatic Ground Environment) air defense system, the topic of their new book, grew out of Project Whirlwind, when the United States Department of Defense realized that the Whirlwind computer might be the core of a continental early warning system. From Whirlwind to MITRE appears in the History of Computing series edited by I. Bernard Cohen and William Aspray. It presents an organizational and social history of one of the foundational projects of the computer era from its initial test in 1951 at Bedford, Massachusetts, to the first installation of a SAGE center and the transfer of development activities to the newly formed MITRE Corporation in 1958.

Aside from its strategic importance, SAGE laid the foundation for mass data-processing systems and was the basis for many computer developments of the 1960s. What started as a new radar system capable of detecting "enemy" aircraft and transferring data over telephone lines and into an electronic digital computer--which then immediately calculated the aircraft's flight path and directed the pilot of a "defending" aircraft to his target--was in fact a revolutionary new approach in data processing that opened up new possibilities.

The heart of the system, the AN/FSQ-7, was one of the first computers to have an internal memory composed of "magnetic cores." SAGE also introduced computer-driven displays, on-line terminals, time-sharing, high-reliability computation, digital signal processing, digital transmission over telephone lines, digital simulation, and duplex computing--all of which foreshadowed the modern computer era. Based on comprehensive material from the MIT and MITRE archives as well as interviews the authors conducted with SAGE researchers over four decades, this book depicts in detail one of the crucial development projects in the history of computing. That alone makes it valuable for every historian of technology.

Apart from the technical accomplishments, the philosophy of SAGE later found its way into military and commercial computer systems. The involvement with the SAGE Project also brought IBM from punch-card machines to computers, eventually resulting in the IBM Model 704 and the SABRE airline reservation system. Furthermore, hundreds of digital-system engineers, thousands of computer programmers, and thousands more digital-computer field engineers were trained in the SAGE development process, people who later gave new impetus to the computing profession. In this respect SAGE is a prototype for the emergence and institutionalization of R&D after World War II. The authors argue that it was the joint efforts of engineers, scientists, and the military, mutually reinforcing, that made SAGE possible and set the stage for a technoscientific tradition that has deeply shaped society over the course of the last fifty years. Whether these developments were to the benefit of us all, as the authors suggest, is one of the few issues that seem questionable. From Whirlwind to MITREhelps to advance and substantiate an important new perspective on the role of organization and management in the history of computing. It is also a book that is a pleasure to read.