Perry O. Crawford Jr.

Crawford continued in IBM until his retirement in 1988 working towards what he saw as a necessary "computer transition" as outlined in his 1979 publication below, but otherwise rarely publicized outside of IBM. In a 1980 interview R. Blair Smith, the IBM marketing manager whose contact with American Airlines initiated SABRE, described Crawford's Imaging project:

The thesis included a description of a matrix "selector switch," for implementing an arbitrary function or control sequence. Independently invented by Jan A. Rajchman, this device was incorporated, with acknowledgments, in the ENIAC. in a 1975 interview, J. Presper Eckert, a designer of the ENIAC, described another contribution:

Crawford left his civilian service in the Navy in 1952 to join IBM. The company had been working with the military on SAGE and anticipated further developments in real-time applications. in 1954 Thomas J. Watson, Jr., son of IBM's founder, oversaw Crawford's placement, along with Hans Peter Luhn, to head the design team for creating a digital computer system for managing American Airline's reservations and ticketing. Named SABRE (Semi-Automatic Research Environment), it soon grew to managing the total operation: flight planning, crew schedules, special meals, etc.

Crawford also contributed to the Moore School Lectures with a talk entitled "Applications of Digital Computation Involving Continuous Input and Output Variables" (August 5, 1946). It discussed such topics as missile and combat simulations and was originally classified as confidential and not published until (Campbell-Kelly & Williams 1985, pp. 375–391). He stressed his conviction that these applications could best be performed with the aid of digital computers, a thesis many did not agree with at the time. He gave a talk at a session on electronic computers at the 1947 conference of the Institute of Radio Engineers on "Applications of Electronic Digital Computers" which was summarized in the program:

When Shannon completed his doctorate, Crawford succeeded him in the Center for Analysis as a postgraduate student. His M.Sc. thesis, "Automatic Control by Arithmetic Operations," (1942), continued the theme:

From 1942 to 1945 Crawford served as a civilian attached to the Navy's Special Devices Section (a predecessor of the Naval Air Warfare Center Training Systems Division) at Sands Point, Long Island. In 1946 this became the Special Devices Center under the newly created Office of Naval Research (ONR). Crawford supervised the Navy Ballistics Computation Program until September 1948 when he accepted a temporary position  with the Research and Development Board of the Department of Defense. As head of the computer section in ONR he came into contact with Jay Forrester at MIT who, with his collaborator Robert Everett (computer scientist), headed a project that had roots in developing flight simulators for pilot training and evolved into the Whirlwind Project which in turn prepared the way for the air-defense application SAGE (Semi-Automatic Ground Environment).

His B.Sc thesis, "Instrumental Analysis in Matrix Algebra" was completed in 1939. In summary:

He entered the Massachusetts Institute of Technology in 1936 to study electrical engineering and came to work under Vannevar Bush with fellow student Claude Shannon on the differential analyzer. The theses for his two degrees are considered to be among the earliest modern computer design documents.

Crawford married Marguerite (Peggy) Murtagh (1924-1979). They had five children.

Perry Orson Crawford, Jr. (August 9, 1917 – December 13, 2006) was an American computer pioneer credited as being the first to fully realize and promote the value of digital, as opposed to analog, computers for real-time applications. This was in 1945 while advising Jay Forrester in developing flight simulators and anti-aircraft fire control devices during World War II, before practical digital computers had been produced. His similar foresight on related issues led to his heading twelve years later the design team for IBM's SABRE project, the ticketing system for American Airlines, the first large-scale commercial application of real-time computer systems, which became the model for on-line transaction processing.