Saddle tank
A saddle tank is a container that has a concave-shaped indentation on its underside to sit in a saddle shape over another container or frame.
Almost all today's motorcycles have saddle tanks, the upper part of the vehicle frame runs through a corresponding recess on the underside of the tank. From the 1930s onwards, the saddle tank replaced the plug- in tank that had been common up until then . This was cylindrical or cuboid and was screwed to the upper frame tube from below with clamps.
Saddle tanks were also used on some English steam locomotives . The fresh water tank sat in the shape of a saddle on the steam boiler of the locomotive.
In the case of submarines , a saddle tank is a storage space attached along the hull outside of the pressure hull , which as a rule was mainly used for bunkering fuel. Here the tank sits in the shape of a saddle on the pressure hull of the submarine. The best example of a submarine with saddle tanks is the type VII of the Kriegsmarine. In the case of the XB type , the saddle tanks were also used to transport freight .