Encroaching the others' lands. The Night's King, along with the white walkers who manned the walls tried to move the wildlings south of the wall. This didnt fit well with the Wildling leader, who plotted with the stark at winterfell to overthrow the Night's King and remove the white walkers from the wall.
Russia was the first to develop an airplane specifically for this purpose: the Murometz, a large four-engine airplane that Igor Sikorsky had developed in 1913 as a passenger plane, was adapted for use as a bomber in 1914 and was used successfully throughout the war.
A hydroplane, or seaplane, is an aircraft designed to take off and land from water. In War Thunder there are a few, and more are planned to be added. Their ability to land and repair in the water (next to an airstrip or a carrier) as well as on land means not only a strategic advantage for their pilots, but also an opportunity for amusement and change of pace in War Thunder.