With a flexible pod, you'd partially deflate it to get it through awkward areas, which would make it negatively buoyant. Once re-inflated to the previous pressu

With a flexible pod, you'd partially deflate it to get it through awkward areas, which would make it negatively buoyant. Once re-inflated to the previous pressure it would be neutrally buoyant once again. Re-inflation could be done via the same gas cylinder that's being used to replenish the air in the pod.