I found a rather embarrassing error in my Mt. Hamilton by Bike publication, so I wanted to set the record straight regarding a fatal plane crash at the Lick Observatory.
I said the plane that crashed was a jet, which would have been impossible on May 21, 1939, when the accident happened. I was also off by a day on the accident. The first jet flight did not take place until August 27, 1939 — the Heinkel He 178.
Someone told me it was a jet and when I did the search online I found the account but did not follow through to identify the plane, which was a Northrop A-17 single-engine Army attack bomber, built around 1935-7. It could also be called a Douglas brand aircraft.
A thorough account of the tragedy was written in The Scientific Monthly, July 1939, and is now available online.