The actual disc is 8" in diameter and has on it....JT3D-1,-3,-3B/DC-8 Gas Turbine Engine Performance Calculator. Flight Operations Engineering. The cover reads reads as per the close-up pic. A rather facsinating old piece of aviation memorabilia.
At Molloy's MEGA ANTIQUES CENTRE, Takapuna, Auckland, New Zealand
Specialists in Pacific Islands Items, Victoriana, And a Fascinating Range of General Collectibles