Frames in the void wing tank of a river barge. In this photo,
the knuckle plate has been cut away so that bent frames can be renewed.
The double bottom is exposed. New knuckle plate will be installed
once the frames are renewed. The USCG inspects all phases of tank barge
repair and construction. This wing tank will be pressurized with air and
each seam will be sprayed with a soap mixture to check for the smallest
of leaks. The hulls of tank barges are literally air tight.
The first 'bottom' may be the one that contacts the water and a void space and the second 'bottom' may tbe the one that contacts the cargo and the void space.