use the ground effect – break your wing tip vortices

Chinese scientists have developed a “wing-in-ground” (WIG) aircraft
that can fly long distances just a few metres above the sea surface,
state media reported on Wednesday.

The
plane can fly as low as half a meter from the ground, hitting speeds of
up to 300 kilometres per hour (180 miles per hour), while also carrying
up to 4 tonnes on takeoff.

WIG aircraft exploit a phenomenon known as the “ground effect”, which occurs as a plane flies close to the ground.

At
a height roughly equivalent to twice the plane’s wingspan, trailing
wing vortices that cause drag are disrupted by the ground. This allows
the aircraft to travel much more quickly through the air and increases
the lift experienced.

The plane is as safe as a ship, although much faster, according to Xu Zhengyu of the research team that developed the plane at Tongji University
in Shanghai. “It can carry much more weight than ordinary planes, while
costing half as much and using half as much fuel,” he says.

The China Daily
reports that the Tongji University plane should consume one third as
much fuel as standard planes of the same size, by harnessing the ground
effect (see Green sky thinking: eight ways to a cleaner flying future).

Wave-skimming plane developed in China – tech – 11 July 2007 – New Scientist Tech