AN / FSQ-7 - the most removable computer in history

Even during World War II, the U.S. Navy made a proposal to the University of Massachusetts on the possibility of creating a flight simulator for training bomber crews. After the success of ENIAC in 1945, it was decided to use a computer for these purposes and abandon unsuccessful attempts to create an analog computer.

The project was noticeably delayed, and was completed after the end of World War II. It remained unclear what to do with the Whirlwind computer created - the military lost interest in the undertaking. Nevertheless, it was of historical importance - it was Whirlwind and the unrealized Whirlwind II project that became the basis of Jay Forrester’s proposal to create an air defense system.

The course of events was accelerated by the fact of the appearance of atomic weapons in the USSR and the frankly strained relations between the two states. As early as December 1949, the Air Defense Committee, headed by George Valley, recommended computerized computing for radar stations. Valley and Forrester actually laid the foundation for the future SAGE system (SAGE), the development of which cost about $ 10 billion in 1954 and included the creation of 24 command centers equipped with an AN / FSQ-7 computer, the size record of which has never been broken .

Computers were a key component of the system. It’s easy to see in hundreds of Q7 panels with their switches, buttons and flashing lights a paradise for the visualization of the movie. And that is why the Q7 is the most rented computer in history. Various parts of it still appear in the frame today, despite the fact that it was created at the dawn of the computer era and was not used after 1983.



In September 1953, based on the unrealized plans of Whirlwind II, IBM signed a contract for the supply of two prototypes. On October 28 of the same year, the Air Force Council recommends allocating funds from the 1955 budget to finance the Lincoln automatic system (renamed SAGE in 1954). In 1955, the SAGE experimental subsector in Lexington was completed, and by October, the AN / FSQ-7 prototype called the XD-1, which originally worked without displays, appeared in Building F.

Air Force personnel trained in Kingston, New York, in 1955. By 1959, 2 thousand simulated intercepts had already been carried out, and the first real one took place in August 1958. Large-scale tests of the mathematical model of the ATABE algorithm (Automatic Target and Battery Evaluation) were carried out using real readings of military radars that spotted training violations of the defense sectors (in particular, the Skyshield military exercises).

Each of the 24 monsters had 49 thousand vacuum tubes inside (together with external systems, each point contained about 60 thousand lamps), weighed 250 tons, occupied 2 thousand square meters (three floors of SAGE fortified buildings located in different parts of the USA and Canada) and consumed 3 megawatts of electricity at the peak, but productivity was high for that time - 75 thousand operations per second, which made it possible to track the position of up to 300 air targets. It was possible to connect 100 operator consoles to the computer, which were a monitor with a light gun for targeting, a cigarette lighter and an ashtray.



To ensure the reliability of the Q7 functioning of the RAM system, control instructions, maintenance, the arithmetic module, input-output control and program elements were duplicated. Thus, each of Q7 was a combination of two independent computers, called the Latin letters A and B. They did not function at the same time: A did the work, while B was in standby mode and could be serviced, then they changed roles. On average, each of the computers consumed 1 megawatt of electricity.

The computer was equipped with an IBM 723 card punch, an IBM 713 punch card reader, an IBM 728 magnetic drum, interchange devices with other SAGE computers, and a light display and warning system, which consisted of several dozen consoles in different rooms.



Using Q7, it was possible to directly launch missiles from the Bomark complex, and computer algorithms automatically controlled the take-off, flight, and the start of a supersonic jump onto a target. Later, a system was implemented to configure autopilots of manned fighters to aim at a target using the ground-to-air communications subsystem.

Q7 possessed Magnetic Core Memory No. 1 - a grid of 256 × 256 33-bit words (65.536 machine words in total, shown in the photo on the left) - and a second smaller module - 64 × 64, 4096 33-bit words . The memory cycle was 3.25 microseconds. His younger brother FSQ-8, which was equipped with control centers of the SAGE system, had two modules of size 4096 machine words. The reason for the presence of two modules was the need to run a diagnostic mode through one of the memory modules. One of the bits of the 33-bit machine word was a parity bit.

To store data, each of the machine words was divided into two halves, in each of them a 15-bit number and a sign bit were stored. Arithmetic operations were carried out on both halves simultaneously. Numbers were represented as fractions from −1 to 1 to avoid overflow during multiplication. Establishing the limits of computation fell on the shoulders of the programmer.

The instructions used the first half of the machine word and the sign bit of the second half to form addresses, which made it possible to use 17-bit memory addressing. The remainder of the second half contained instructions. The first three bits of the second half after the bit of the sign determined the index register, the next - the instruction class, its type and supporting information. Addresses were written in octal, where two bits formed the prefix.

Also, the machines had 12 magnetic drums: 6 for the display system, 6 for the computer itself. Each of the drums had 33 heads and several spare ones, which made it possible to quickly read a 33-bit word. The full SAGE system was deployed in 1963. Ironically, the network of tube computers not only managed to become technically outdated by this point, but the meaning of such a system was lost due to the appearance of intercontinental ballistic missiles and the apparent threat to the reality of their work in the form of "Satellite-1" (the so-called "satellite crisis") , as well as a fanatical belief among the highest Soviet leadership in the universality of ballistic missiles to the detriment of manned bombers.





For all the technical beauty, computers had a whole family of drawbacks: it was the short life of vacuum tubes, which required an automatic diagnostic system, and huge energy consumption. Once when testing in Newburgh (NY), the computer was connected to the wrong phase, which led to the failure of the line switches to Pennsylvania itself. Each of the machines required a staff of approximately 60 people, divided into three groups: the computer itself, I / O and displays. Also, in 1964, during the test, an error was detected in the processing of flight paths: when several technical conditions coincided, they were often discarded.

In the end, SAGE, for which more was spent than the entire Manhattan project, was phased out. The AN / FSQ-7 computers were gradually replaced by the BUIC system (Backup Interceptor Control System), however, two Q7s were serviced until 1983.

Technology introduced in AN / FSQ-7 was used in the Saber ticketing system created by IBM in 1964. Q7 pushed the world to create many technologies and was the first distributed network of computers using a telephone line for communication, which was the prototype of modern modems. Q7 used new magnetic core memory for that time, interactive graphic displays, network databases, multi-tasking systems, structured software modules and modular computers. Thanks to the SAGE project, the profession of software engineer and light gun was invented by Robert Everett.

Of course, AN / FSQ-7 left a huge mark on computer science, but much more interesting is what became of the computer after his death. Surprisingly, despite the fact that the machine was developed in the 50s of the last century, its fragments are still used to create the atmosphere of a futuristic supercomputer, or at least to create the effect of equipment of a later era than the one that Q7 got into.

For example, the panels of a lamp computer are used to create the effect of the 21st century. In the comedy “Sleeper” of 1973, where Miles Monroe (played by Woody Allen) falls asleep in a cryogenic chamber for 200 years and ends up in 2173, quite a lot of equipment from Q7 is used: this is the command post panel, and the section duplex service console indicators.





Mike Leuven, who served in the US Air Force in 1982-86. and one of the last to catch the last working instance of AN / FSQ-7, he first noticed the familiar panels in the mid-60s era series The Time Tunnel and became interested in what other films this tube monster played. In the Temporary Tunnel, Q7 plays the role of a secret government project for a time machine under the Arizona desert. The appearance of the AN / FSQ-7 computer would be most logical in the film “Doctor Strangelove, or How I Stopped Being Afraid and Love the Bomb” - then he would fulfill his direct function of air defense, but Stanley Kubrick’s comedy uses the old IBM 7090/94 .







One of the most popular works in which Q7 appeared is the 1996 Independence Day. Although the last computer in the series was stopped 13 years earlier, in the film it plays the role of a modern command center. The 1983 film “War Games” is full of many flashing panels, screens (what the main character stands for - the WOPR defense computer), but the Q7 has nothing to do with them, it appears in the form of control panels for the main magnetic drum and circuit indicators only in an archived video with Professor Falken. AN / FSQ-7 - and still a frequent guest of the screen, for example, he was seen in the TV series Lost ("Lost"). It appears as a whole group (from left to right) of power panels, manual testing of drums and radar panels.











How did the equipment from a secret defense computer so quickly get into the frame of mass cinema? The best known are the two companies that owned the panels and parts of the decommissioned Q7: Vectrex Corporation and Woody's Electrical Props . The first company from Santa Monica rented computer parts for, for example, the Battlestar Galactica, but in the 80s they went out of business and sold the remaining equipment. Some of the panels were purchased by individuals .

" Woody 's electrical props"Provided parts of Q7 for films about Austin Powers, WarGames (War Games), Apollo 13 (Apollo 13) and the series Lost (Lost). In the early 60s, Twentieth Century Fox acquired the decommissioned AN / FSQ-7, the panels of which were later purchased by Woody's props specialist. Since then, some of the panels have been replaced, and Mike Leuven provides photographs of Woody's props .

According to the materials of the report Introduction to AN / FSQ-7 Combat Direction Central and AN / FSQ-8 the Control Central Combat , the IBM-the SAGE-Computer , plyojump.com , memories of Pete Karkuliasa, Q-7 Equipment for the years 1967-69 , of Wired .com , Mike Leuven’s list of IBM AN / FSQ-7 media appearancesand the Starring the Computer site listing of IBM AN / FSQ-7 media appearances .