They say they lined up on runway 18 which is now runway 19 so they were flying almost directly south. That doesn't really clear up how they had any ambiguity ab

They say they lined up on runway 18 which is now runway 19 so they were flying almost directly south. That doesn't really clear up how they had any ambiguity about what direction they should go to follow the river though because for a decent ways you're already following the river downstream.