Twenty years ago, in the early days of the internet, a physics teacher with an interest in aviation history started building a list of U.S. aircraft serial numbers, matching them to the aircraft type, and researching the history and distribution of each individual plane. His list—and his name—became famous in the online aviation community as the go-to reference for what a plane was, where it was sent, and what happened to it. The list was always bare-bones: a tabbed HTML file with the barest of formatting, but he updated it frequently. I went looking for a serial number the other day and my decades-old bookmark led to a broken link; some further searching revealed Joe Baugher had passed away from cancer in 2023, and a new historian took over the list at a new URL.