Vol.6, No.2 of the IBM Systems Journal (from 1967) describing the system
and programs
All that hardware has been replaced, but the software, which first went operational in the early 70s, is still in use but now in duplexed 370s instead
of multiprocessor 360s. The multiprocessor was always a rotten idea, since there wasn't enough hardware to configure two complete systems. This was done supposedly for efficiency, but the consequence was that there was no way to test a new software delivery except to take the system down. We told them that but the guy in charge wouldn't listen.
***
I did alta-vista search on 9020 and came up with a couple hits.
http://www.faa.gov/apa/speeches/aoa/FWINGS.htm
Automation of en route ATC began with the installation of IBM's prototype 9020 system at the Jacksonville Center in 1967. Designed to provide automated flight data processing and radar tracking at all en route centers and major terminals, this was the most complex computer application ever undertaken up to that time. Its half million commands required more than twice the amount of memory originally planned, a complication which caused the project to fall behind schedule. The installation at all 22 en route centers was not completed until the end of the 1970s.
http://www.aero-space.nasa.gov/library/ch1.htm
Automation of en route ATC began with the installation of IBM's prototype 9020 system at the Jacksonville Center in 1967. The system was designed to provide automated flight data processing and radar tracking at all en route centers and major terminals. The system was delivered behind schedule, which created significant frustration within FAA, the aviation community and IBM. The system would not be in place at all 22 en route centers until the end of the 1970s. However, indicative of the complex nature of automating the en route environment, the 9020 system proved to be the most complex computer application in the world at the time, with more than half a million commands. When the program was completed, IBM had more than doubled
the amount of memory the company had first thought the program would require.
http://api.hq.faa.gov/96sp-fin.htm
http://catless.ncl.ac.uk/Risks/5.67.html
http://home.columbus.rr.com/lusch/index.html
HOCSR (Host and Oceanic Computer Replacement System)
http://www.faa.gov/aua/ipt_prod/enroute/hocsrfct.htm
A system-wide upgrade completed in 1999 at the 20 Air Route Traffic Control Centers. It is the heart of the system in that it receives, processes, coordinates, distributes and tracks information on aircraft movements throughout domestic and oceanic airspace. It replaced the HOST computers that ten years earlier had replaced the old IBM 9020
computers.
HOST
A system-wide computer upgrade completed in 1989 at the 20 Air Route Traffic Control Centers. HOST replaced the old IBM 9020 computers. It has
since been superseded by HOCSR.
http://www.faa.gov/aua/ipt_prod/enroute/hocsrfct.htm
***
I have no idea what came first or why. But this is the chronology of the 9020:
We (MITRE) wrote the specification for the Central Computer Complex (the official name of the 9020, commonly referred to as the CCC [1]) in the spring and summer of 1963. The spec pretty much demanded a multiprocessor because the guy in charge at FAA had fallen in love with the Burroughs computer used in BUIC. (What was it called? D850?).
The contract was awarded to IBM in the summer of 1964 and the first one, a 9020A all 360/50 system, was delivered to the National Aviation Facilities
Experimental Center (NAFEC) near Atlantic City in the summer of 1965, and software development started.
[1] I named the CCC. It happened this way. In February of 1963 we started work on the spec for a computer for the new system. We quickly realized we had a problem discussing it because we didn't have a name for it. There was a meeting in Howard Kirshner's office in MITRE/Bedford to decide on a name. Various options were kicked around but none made a satisfying acronym. My boss was politically very liberal, a declared socialist, ACLU member, etc., while I was a Goldwater conservative. We regularly good-naturedly sparred and needled one another about politics. Suddenly I had an inspiration, looked my boss in the eye, and said, "If we name it the Central Computer Complex then we could call it the CCC." He immediately picked up on the joke (the Civilian Conservation Corps was a Roosevelt New Deal program) and supported my suggestion. We carried the day and the CCC was in due course followed by the CDC, the DCC, the ACC, and the TCCC.