Now, I do reckon that there is a Douglas RD-2 from early thirties. Boat in b/g is just as interesting. More later... if I type too much, someone else'll beat me to it
Yup - Douglas RD-2 or -1 (USN/USCG designation) aka Dolphin. Built around 1931, about 60 made; 25 or so for US Army (designation C-21/6/9); similar amount to USN/USCG; remainder as commercial haulers of SLF (wet). Remarkable safety record in airline use and some fame too: a USN RD-2 was used by F D Roosevelt as, allegedly, the first -ever presidential aircraft (Seaplane-One??) in 1933. Others were customised for the rich, famous and/or discerning including William Boeing and the Vanderbilts. A couple somehow found their way to the RAAF to serve in WW2.
Smashing-looking machine - a real boat hull (all metal with watertight bays) and wooden wing. Initially powered by pair of 300hp Wright J-6 radials, variously upgraded with other Wright and P&W lumps, most potent of which were two 550hp Wasps
Take that wing off, fit a couple of Volvo Pentas amidships and you'd get yourself a very quick launch.
Talking of which, the boat in background is, I believe, a USCG picket boat designed and built by the Beals of Maine (two Packard straight-eights; 35+ kts). I confess a personal advantage here, since my boss is the boat designers' grandson and I am restoring some late 20s photos of the vessels.
So insomnia, and inside knowledge, does have some advantages!
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