<p>Cockpit photo of the KC-97 at Castle Air Museum, formerly Castle Air Force Base.
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The cabin was mostly filled with the big, cylindrical, fuel tanks, upper and lower, on the port side of the fuselage, on the main deck level. I expect they are baffled and or subdivided to prevent fore-and-aft sloshing too.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/9998127@N06">Bill Abbott</a>
<a href="//commons.wikimedia.org/wiki/Flickr" class="mw-redirect" title="Flickr">Flickr</a>: <a rel="nofollow" class="external text" href="https://www.flickr.com/photos/9998127@N06/4415814271">00-07-02 KC 97 cockpit</a>