dsc73910.jpg

Partial walk-around of one of the Y-ring segments.

Picture 2 of 3.

The bottom label reads "Saturn V Skin Segment" and the upper label reads "Saturn V Booster Y-Ring."

The Y-ring was a large ring, a single piece which formed the upper- or lower-most portion of the cylindrical section of the propellant tank. This solid, continuous ring was welded to the tank wall. I'm uncertain as to why there's a "stair step" leading to the Y-ring segment. The base leg of the Y-ring would have been welded to the end of the tank wall cylinder.