The Secret History of the First Microprocessor, the F-14, and Me

The story of the first microprocessor, one you may have heard, goes something like this: The Intel 4004 was introduced in late 1971, for use in a calculator. It was a combination of four chips, and it could be programmed to do other things too, like run a cash register or a pinball game. Flexible and inexpensive, the 4004 propelled an entire industry forward; it was the conceptual forefather of the machine upon which you are probably reading this very article.

That’s the canonical sketch. But objects, events, people—they have alternate histories. Their stories can often be told a different way, from a different perspective, or a what could have been.

This is the story, then, of how another first microprocessor, a secret one, came to be—and of my own entwinement with it. The device was designed by a team at a company called Garrett AiResearch on a subcontract for Grumman, the aircraft manufacturer. It was larger, it was a combination of six chips, and it performed crucial functions for the F-14 Tomcat fighter jet, which celebrates the 50th anniversary of its first flight this week. It was called the Central Air Data Computer, and it computed things like altitude and Mach number; it figured out the angle of attack, key to landing and missile targeting; and it controlled the wing sweep, allowing the craft to be both maneuverable when the wings were at about 50 degrees and very, very fast when they were swept all the way back.
Ray Holt was one of the engineers for the Central Air Data Computer. He is probably not someone you have heard of—how could you have? He worked on the project, one of two people doing what’s called the logic design, for two years, between 1968 and 1970, with a team that included his younger brother, Bill. He couldn’t tell anyone about what they had built. The project was kept quiet by the Navy and by Garrett for decades as other engineers were awarded credit for inventing firsts. Later, when he was able to talk about the device, people were skeptical. Maybe they were uncomfortable with history being revised.
I wanted to know more about him. Ray has always been in the margins of my life, ghosting around the edges of my consciousness. I remember visiting his parents’ house in Compton, California, when I was very young. His family came to our place once, and I have a memory of chasing one of his three sons up the stairs. One time, when I was in my mid-twenties, I unknowingly sat next to him in the audience at a health food talk my mother was giving. She was surprised to see us sitting together when she came out afterward to say hello.Ray Holt is 76 years old now. He lives in rural Mississippi, where he teaches high school STEM classes and runs a robotics nonprofit. Me, I live in the San Francisco Bay Area, with my husband, a software engineer, and two sons; I’ve been an editor at WIRED for more than a decade. Ray and I reconnected over the summer, and after he told me his story, I wanted to learn more about the Central Air Data Computer and its place in history—and how his life might have branched around mine.
His career as an engineer almost didn’t happen. Growing up in Compton, Ray made extra cash fixing bicycles and old tube radios; in high school he was class president and a great baseball player, but he was also a B student who had difficulty reading. His teachers sometimes discounted him. One once said to him, “I wish you were as good a student as Bill.” Everybody loved Bill. Math genius, they said. When Ray took an aptitude test during his senior year, he was told that he had low mechanical ability. He was told, “Don’t go into engineering.”