While there where a lot of bouncy (but fully covered boobies) in episode #4, I find it interesting that with Ranka and Sheryl, the producers have gone out of their way to avoid fanservice upskirt panty shots so far despite many opportunities (refering to the anime, not the manga, which is a whole different kettle of fish).
There's been a few times so far when Ranka has fallen down and although her skirt has risen up, they have stopped short of showing her panties.
Same with Sheryl. In the scene where she jumps into the shelter, she makes a point of pulling down her skirt, so her panties can't been seen. In the zero-g arrival scene in episode #1/Deculture edition, they preserve Sheyrl's dignity and don't let her panties show.
Graham