A lot of
theoretical research has been done concerning ground effect in relation
to stability and related topics, but very few Wing-In-Ground effect
crafts exist. At the same time, the search for faster and faster
machines has neglected the effect, sometimes with devastating results.
In 2001, Mercedes built three Le Mans cars. Two of the three cars
flipped over backwards during the race. Almost every year, several high
speed racing catamarans flip. Even small racing hover craft at high
speed have the tendency to lift at the front, but this twisting moment
can be compensated by the driver leaning his weight over the front of
the craft. Spectacular crashes from instability need not be the norm.
Some time ago, a Russian company built the SERVER, a typical dynamic
hover craft. Cruising speed 120 km/h with only 54 HP. As you see on the
image, the propeller and engine are in front of the craft, pulling the
craft instead of pushing it. This pulling configuration is far more
stable and could be incorporated to create stable WIG craft designs.
Second, by installing a folding skirt in front, the craft could utilize
static pressure to achieve separation from water surface tension, and
to maintain elevation until the craft is traveling fast enough to
maintain dynamic lift. The skirt could be raised and the craft could
travel in WIG mode. If used only on water, a catamaran configuration
will work well. Surface Area, Desired Speed, Cruising Altitude, Pay
Load, Cockpit Size, Horizontal Stabilization, Flaring Height and even
ergonomic, are only some of the factors that need to be considered for
an excellent WIG design.
An other example of original thinking is shown on the right. The
Cushion Crow is a flying body/wing.Experiments with this design are
very promising. These are only two examples. There are many more
possibilities. Warning model experimenters: Due to the behavior of a
wing in ground effect, models can only be used on flat water or the
model must be a large scale.
Cushion Crow
Most models are low flying aircraft's !! BUT.........
for a firs dry, go to this link for an easy to build paper model