SAGE

The heart of SAGE

The very heart of SAGE—the AN/FSQ-7 computers—performed with keen accuracy as well as extraordinary reliability and durability over a generation. Installed in the 1950s, the last AN/FSQ-7 was decommissioned in 1983; statistics show the computers operated at an average 97 percent run time. Downtime for the AN/FSQ-7 averaged less than four hours per year. Even in the 1970s, other computers “frequently counted yearly down time in weeks.”

From SAGE to Sabre

The work involved in SAGE led to the introduction of computers and modernization within the airline industry through Sabre, a computer-based reservations system that was first developed for American Airlines and debuted in 1960. Today, the system is involved in every conceivable facet of commercial travel.

Blockhouse: exterior view

SAGE sites around the country were embedded into the landscape and hardened against attack. The computer itself occupied an acre of floor space. At Camp Adair in Oregon, more than 1000 men were stationed at the SAGE site, then called “Blockhouse”. The Blockhouse was responsible for the defense of eight western states, and could scramble U.S. fighter jets from its location, as well as San Francisco’s Bay Area; Fresno, California; or Boise, Idaho.

Courtesy of The MITRE Corporation

Blockhouse: schematic

Improving performance: the SAGE benchmarks

SAGE also brought forth a series of standards that would inform production and performance of future IBM computers, and thus influenced the entire industry. For example, “SAGE benchmarks” guided IBM researchers studying the degradation of early operating software performance when used in large networks to complete asynchronous but parallel tasks.

Magnetic core array

SAGE used IBM’s magnetic core memory (iron oxide “cores” representing bits of information), which became the predominant technology for computer main memory from the 1950s into the early 1970s. It allowed for data retrieval in millionths of a second, an enormous leap over previous technologies.