Ekranoplan

Nothing quite like sitting by the water side and watching the ekranoplans thunder past.

— Ener Gokay, aviation enthusiast

Thanks to the so-called ground effect, airplanes become more efficient when near the ground, i.e. when flying below a hight equal to about half their wingspan. This means that an ekranoplan, as vehicles designed specifically to utilize this effect are called, can travel a longer distance or carry more weight than an airplane of similar weight.

Sea Travel

Because of their low flight, ekranoplans are best used above water. By taking off and landing on water, they also circumvent the need for a runway, which would be quite large for this size of vehicle. Large ekranoplans run along the coastlines of Kent Prime and Sharov's World. The very largest models, which are less susceptible to waves, also travel across the ocean between continents. These ekranoplans are the largest heavier-than-air aircraft ever built.
The ekranoplans used for sea travel typically can carry several hundred passengers, up to 1100 for the largest models, or an equivalent amount of cargo. They are powered by an array of up to a dozen hydrogen powered jet engines located near the front. During takeoff, these push air under the wings to amplify the ground effect. Once the vehicle is up to cruising height and speed, most of them can be powered off.

Inland Travel

Where possible, the use of ekranoplanes for inland travel is avoided, since it comes with many complications. Instead, autogyros are used. These have a significantly lower cruising speed, however. On Toliman Prime, which does not have large contiguous oceans like the other planets, this necessitates the use of ekranoplans across land for larger distances.
Ekranoplans can in fact fly out of ground effect to some extent. While this is less efficient, it allows them to "hop" over obstacles, such as small mountain chains. By carefully plotting a route between the many lakes and rivers of the planet, large distances can be traversed safely. Since there is no large vegetation as obstacles, ekranoplans can also fly in ground effect across land, where it is flat enough. The models used for inland travel are usually smaller, to improve maneuverability. They still rely on water for takeoff and landing. Most commonly they are powered by a propeller engine when cruising in ground effect, and may use a jet engine in addition to it for takeoff and to achieve the extra power necessary when flying out of ground effect.

See Also