Saturn V S-II Upper Stringer Dimensions

[daknife]

In building a scale model of the Apollo 11 Saturn V I have found that the upper stringers on the S-II stage are 131.42 inches long. The lower part of these stringers are covered by the LH2 tank installation. Also, there are longerons between the stringers in some locations.

I've been unable to determine the length of the stringers that are covered by the insulation and the locations that the logerons are used. If someone could help me out with this I'd appreciate it.

[John Duncan]

The area of stringers covered by the insulation is approximately 33 inches.  The T-stringers in between the hat channels cover the circumference except underneath the telemetry antennas and several feet on each side of the access hatch on the Position  II near the umbilicals.  I'd try looking at stage stacking photos to nail down the exact location of the T stringers.