Here's a small pamphlet put out by Pratt & Whitney to
their JT3D airline customers. Their purpose was to help
publicize the new turbofan engines that were being installed in large numbers on
the DC-8-50 Series and various 707"B" models at the time.
covers were individualized for each airline -- TWA in this
case -- but inside the content was identical for all.
front cover of this example captures not only the essence of the DynaFan trademark, but also
the distinctive shape and lines of the B707/720-B forward engine