American Military Helicopters
E.R. Johnson’s American Military Helicopters is one of those giant encyclopedias of aircraft that appeal only really to a certain group of people, but which appeals a LOT to said group. This is a huge catalog of everything that has either had a rotary wing or a vertical takeoff feature that either entered or was considered for American military service.
So you get stuff like the UH-1 and F-35B. But you also get obscure projects from the 1950s and 60s that ranged from gargantuan lifters that challenged the Soviet monsters in size to literal flying jeeps. The history nerd in me complains that it didn’t go as far into the VTOL weeds as it could have, but as an expanded “coffee table book”, it’s excellent for what it is.