Cant operate in stormy weather either. It was just a military tech show-off peice, really. That's why it got funding.
The idea of the ekranoplans was to cover open ocean distances rediculously fast (compared to boats), be nearly invisible to radar (at the time), and to deposit large payloads (compared to other aircraft.
-It was low enough to be below terestrial radar.
-It wasn't "in" the water, so sonar didn't pick it up.
-Flew as fast as a plane.
-Rode on a dense "cusion" of ground effect air, so less lifting surface was needed.
The one in thos pics was fitted with missles because FUCK YEA, that's why!
It was rendered useless by anything that wasn't perfect flying conditions.