On the left, you can see a small electric craft hovering over a pencil. On
the right, you can see two different styles of pumping air into a bag-skirted
hovercraft's air cushion. The smaller vehicles are store-bought toys, and
they use flow-through skirts, where first a fan pumps all the lift air into
the skirt and then the air flows through holes in the skirt to create the
crafts' air cushion, and then finally the air escapes out from the air gap
between the skirt and the ground (or other surface). The larger two
pink vehicles are homemade electric hovercraft models, and each uses the same
skirt system as my full-size Weber Starcruiser -- some lift air is pumped
into the skirt (which is sealed across the bottom -- no holes) and most
of the lift air is pumped directly underneath the craft to create the air
cushion the vehicle uses to hover. Flow-through skirts are less popular
on full-size crafts (their holes can catch on obstructions, and
they allow water to enter the skirt while off cushion on water and often do not
allow the water to drain out when the craft gets back on cushion) but they are p
opular among store-bought
toys (perhaps because these are less likely to be used over water).