"Inaccessible" Schloss Adler
If Schoss Adler was truly "inaccessible" as they say in the beginning film, we would have to believe that medieval builders were in the practice of construction castles no one could either enter or leave, let alone build. Unless, of course, they had some kind of medieval cable car or helicopter.
AND ANOTHER THING! --
When first commando was killed right after he landed by someone staging a broken-neck-accident, how were they able to do it without leaving a tell-tale trail in the snow?