Okay. The scene at the beginning of Where Eagles Dare when the German officer arrives at the mountain fortress in a helicopter (Bell model 47) just ruins what was a pretty good flick.
I passed that off as Just Plane Wrong due to the filmakers unable to locate a Focke-Achgelis Fa223. I was more irritated by the very long shot of them escaping supposedly in a Junkers Ju52/3m, so distant that it was unidentifiable, but the raising of the undercarriage could still be seen. You actually have the use of a DC-3 (used for the parachute into Germany scences), and can't do that off camera?
Also Richard Burton looking into the dark by holding a match 3" in from of his eyes. and the standard explosive charges, which, depending on script, either bring down half a castle, or cut though a telephone pole to fell it with surgical precision..