Monocock
Hi Desert,
Sadly, Mr Druine is dead. If he wasn't, I'd happily pass his contact details on to you as I'm sure he'd welcome your technical views on this matter. As it stands, his design is well proven, so we feel quite happy to go along with it.
The fuel tank in my Cub is in exactly the same place too. Mr Piper built a few Cubs with such fuel tank locations, so we feel reasonably happy that it'll be ok.
That location was typical in older designs for many reasons. I flew a Porterfield Turner with C65 that had the tank in the same location. Delightful little airplane, but I still didn't like the location for obvious reasons (but at least it didn't hold much fuel
). The Beavers and Otters (two of my favorites) required you to basically sit on the tanks, and I really didn't have a problem with that as the airplanes were brilliant in so many other ways. The tank location actually made sense given the purpose and planned working environments of the airplanes.
Enjoyable thread to read, and I hope you continue to illustrate and describe the fine, restorative work you are doing. Disregard the dis. They're everywhere in life, and occasionally there sometimes seems to be more than their share on PPRuNe.