Factual error: Most of the time the boys have no visible breaths, even though they're in a freezing climate.
Revealing mistake: When Roy digs out Antonio in the snow, you see his mouth move although he's dead.
Factual error: While debating when to begin the trek across the Andes with Nando, Roberto remarks that "winter will be over" soon. This incident took place in South America where the seasons are opposite from the northern hemisphere. The plane crashed in the spring and Nando and Roberto reached Chile by foot in the summer.