Although the film is supposed to take place in the summer of 1943, the plane Lt. Commander Staves disembarks from on the Isle of Pines carries post-World War II national insignia on its fuselage and wings.
When Lt. Commander Staves, Lt. Commander Evans, and Ensign Duncan are seen driving along Havana's shoreline, they're in a post-World War II model jeep.
The M1 (or M2) carbines used in the film have post-World War II bayonet lugs on their barrels.