U.S. Air Force XC-99 Cargo Plane Cockpit Cutaway, 1951

Only the cockpit of the XC-99?  Well, this plane was so freaking huge, we can barely show more than this.

Based on a B-36 bomber, the XC-99–built by Convair–flew 7,400 hours over the span of about 10 years.

Click to Enlarge to 786 x 742 px:

Source:  Popular Science March 1951