The invention relates to an underwater antenna device with a nonstationary antenna, an extension mechanism and a repositioning mechanism, wherein an extending force can be applied in a direction of the extending force by the extension mechanism of the antenna and an opposing force can be applied in a direction of the opposing force, in the opposite direction to the extending force by the repositioning mechanism of the antenna, characterized in that the repositioning mechanism or a part of the repositioning mechanism is designed as selectively nonstationary, so that, by selected changes to the position, the antenna can be positioned in a retracted position, an extended position or an intermediate position.