There was a whole writeup (on here, IIRC) about the engineering behind the only (or one of less than a handful) types of planes that can transit Antarctica during the cold, dark months.

The fuel freezes, the oil freezes, the rubber in the tires and gaskets becomes brittle, and basically nothing normal works. I recall it being similar-but-different to the SR71 modifications, where the parts are loose and continuously leaks fluids because the materials all change shapes so much in the environment they're designed for. And of course it all has to return to the initial state for (a safe) landing.