Seriously though, didn't Lockheed make a study of an amphibious Herc some years ago?
To improve still further the versatility of its C-130, Lockheed-Georgia undertook, between 1964 and 1973, several studies of an amphibious version. The basic principles of the conversion were proved during the course of a 1968 US Navy contract for which a on-sixth dynamically scaled, radio-controlled model was used as a development tool. Retaining the basic C-130 airframe and undercarriage, the HOW (Hercules-On-Water) was to be fitted with a retractable hydro-ski beneath the fuselage, a false hull beneath the existing pressurized fuselage, and two auxiliary floats each housing 400 US gal (1,515 litres) of fuel. Furthermore, the nacelles for its Allison T56 engines were to be inverted to take the propellers and intakes away from the water spray. The design was improved during the following four years to include enlarged tail surfaces, double-slotted flaps, and spoilers. Various configurations were offered to military users and airlines, but no production contracts were received.
http://atomictoasters.com/2013/02/he...es-for-a-swim/