Continuity mistake: When the bobsled team is getting their act together in Calgary, there's a scene of them pushing off with an unpainted bobsled. In the shots of the feet of the guys pushing at the back of the sled, you can see that the lower back of the sled is painted black with green stripes, the colours that they paint the sled in a scene a few minutes later.
Plot hole: A nuclear armed stealth fighter is accidentally sent back in time to 1940's Nazi Germany. After the Nazis capture it, two days later they drop a nuclear bomb on the United States. There are several basic problems here. Firstly, if the Nazis captured advanced technology, wouldn't they spend more time taking the plane apart and interrogating the captured pilot? How on earth did they manage to train a pilot to fly the stealth in such a short length of time? And how did the stealth fighter manage to reach the U.S. from Germany when in-flight refuelling was unknown then?