After the ship crash lands on Tau Ceti (damaged as it was from the magnetic disturbances), Barbarella decides to leave the ship and explore. She enters a simple airlock and then opens a circular aperture door on the far side. Unfortunately we never see the controls. The door is a few feet up on the side of the ship, and Barbarella must step down. It is not clear if there is an alternate or accessible method of exit in more standard landings.
When we see her re-entering the door later, the tail of the furs she wears gets caught in the aperture. This suggests that it is a manual or a time-based control rather than a smarter sensor or artificial intelligence like Alphy.