Hmmm. That's only 11 months after the first microprocessor -- Ray and Bill Holt's Central Air Data Computer for the F-14 -- flew for the first time. (Dec 1970)
I’d argue that 1. It wasn’t a microprocessor, and 2. There is no point counting “secret hardware”, same way we don’t include never released prototypes.
[https://www.wired.com/story/secret-history-of-the-first-micr...]
The 4004 might have been first if Intel hadn't been sidetracked to consider a CPU chip for Datapoint. Then TI got involved.
[https://web.archive.org/web/20150512143915/http://thetrendyt...]