It attains level flight near the surface of the Earth, made possible by a cushion of high-pressure air created by the aerodynamic interaction between the wings and the surface known as ground effect.
That's what I'm saying, there is not much in the "Up or Down" maneuverability of this thing, easy pickings for an aircraft that has lots of "Up and Down" maneuverability.
Ground effect works great as long as there are no waves or sand dunes.
International Maritime Organization recognizes three classes of ground effect craft:
1.Type A cannot operate out of ground effect.
2.Type B can jump to clear obstacles by converting kinetic energy (speed) into potential energy (height), but cannot maintain flight without the support of the ground effect.
3.Type C are certified as aircraft, with the ability to operate safely and efficiently out of ground effect.