OK, I cheated a bit on this entry for the A to Z Challenge, since it's not a UFO, it's a flying saucer. Specifically, one designed for a crew of 1 to 3. The entrance is open and stairs are extended; fuel tanks are connected with tubes to the saucer's underbelly. I thought about adding a catawalk to this one, too, but decided that the saucer itself provides a second level to the geomorph.
Place a couple of these next to each other to represent a large hanger bay.