Greybeard- my apologies- it's about 18 years since I operated through Anchorage to Japan. It wasn't Nome, I think it was Bethel where you usually coasted out. Turning onto a direct track from near ANC for the coast out position, then inadvertently maintaining this heading instead of Nav would result in the final position. Easy to do, and it fitted, and in my mind a far more likely event than any other possibility, as indeed was generally recognised at the time. We had a plane that had some sort of mess up on its alignment and tried to continue out of ANC. They gave up and dumped fuel and returned.