At this time, passengers are using the rear door of the Q400 to board and deboard the plane. In real life, this is not the case and passengers are always using the front door. This is the case because, the rear door does not have the build-in stairs, but the front door does. The rear door are also more narrow and the front are much wider. This practise is always used and ofcourse, should be used here too. It is true that the rear door can be used too, but the game does not have the equipment needed. I provide some pictures for illustration.