...but not much in the way of historical detail. I spent about an hour on the net this morning seeing what I could find about the history of UDT swim fins made by Voit Rubber Company, and ended up more confused than ever. So, there's work to be done, or maybe someone out there has first hand knowledge they could pass along.
Churchill fins were the first to be used in U.S. military application, from what I can discern. These shots are from WWII, but no specific date was given.
Two "transitional era" photos, when both Churchills and UDTs appear to be in use by the Navy Seals. Again, no date given.
The earliest clearly dated photo I could find depicting what appear to be UDT fins in military use is 1950. Those suits look like a nightmare to use...
50's era training photo.
No date on this photo, just the US Navy ID in the corner. It's hard to bend a UDT fins with your hands, so either this guy is really strong, or they were using softer rubber back when this was taken. Maybe an experienced diver could date the scuba gear?
No date on this print advert, but I looks pre-1960. The fins are called "Duck Feet," yet the manufacturer is not "Voit," but "Spearfisherman." Some Wikipedia clarification is here...
This is from a vintage diving site...look like UDTs to me.
This is a Vietnam era photo, showing Navy Seals with UDT's.
I would date this ad as mid-70's, based on the graphics. (Just an educated guess.) Swimaster was Voit's dive company name, and the fins, which are what we call UDTs, were called Duck Feet in the ad. The smaller, sleeker surfing/swimming Duck Feet were at least 10 years old by this point, so I'm not sure why they used the same name. Maybe because diving and surfing were two different marketing demographics?
The same brown Swimaster UDTs as shown in the above print ad. No date on the photo, unfortunately.
Even the modern UDTs have the Duck Foot name on the shipping box.
This Voit ad, which is recent, makes the clear distinction between Duck Feet and UDTs.