The interior B17 scenes in the film's opening scene were shot in "Texas Raiders," a B17G bomber which the production team flew for several hours as they needed in-flight footage to match the continuity of the scene. Texas Raiders crashed in Houston a year later, making "Condor's Nest" the final film in which the airplane appears.
The shot of the Nazi flag unfurling over the Pacific coast of South America was a last-second decision after director Blattenberger grabbed the flag out of the prop box on a whim as the crew left for the airport. The crew spent two days location scouting and drove hours into the sand dunes of Paracas, Peru, to achieve that shot.
The Buenos Aires bar in which Jorge Garcia performs as its proprietor is the same bar that features in Sony 's "Point Man"
(2019) where it was a GI bar in 1960s Saigon. The crimson bull from the original set is visible in the background, but with the words changed from Vietnamese to Spanish.
Jacob Keohane's scene eating a sandwich in a Buenos Aires cafe required multiple takes, during which he was forced to down five or six entire egg salad sandwiches, due a miscommunication with the props department which was supposed to acquire a more palatable tray of turkey sandwiches.
Arnold Vosloo, James Urbaniak and Bruce Davison, who didn't speak a word of German prior to accepting their roles as Germans, learned the entire farcical archaeological discussion in German.