Page 61 - Theory and Design of Air Cushion Craft

The future 45

have been used to deliver plant and major construction modules, and as drilling rigs
in these areas. On beach areas, which conventional craft have difficulty in accessing, the
ACV can be used as work boat, communication vessel and exploration survey craft,
and even as air cushion oil exploration platform. Hover platform payload require-
ments are generally in the range of 100 to 250 tonnes, although if the market were to
develop in the future then 500 to 2000 tonnes would be a more useful unit for wider
application.

Arctic transport

The ACV air cushion platforms can be used on ice as transport and communication
vehicles. They can also be used as ice breakers at high or low speed using two differ-
ent mechanisms for breaking the ice which are exclusive to these vehicles. The ACV
Waban Aki operates successfully as a high speed ice breaker in Eastern Canada. This
application generally demands craft with a payload in the range 5 to 30 tonnes.

Work boats and other special applications
The ACV can also be used as a utility work craft, as a multipurpose craft for the pur-
pose of rescue, ferry, security, border defence, hunting, flood and mud survey, etc. The
main market for this type of craft is in the payload range between 500 kg and 5 tonnes.

Load transporters

Air cushion technology can also be applied to carrying modules, heavy equipment and
components in warehouses and workshops. To achieve this, an external source of
compressed or blown air is fed to an air cushion pallet or collection of pallets linked
together under the load. Such equipment can be designed to lift loads between 1 and
10 tonnes. Water cushion pallets using the same principles can be used for movement
of much heavier loads.

1.8 The future

The advent of the hovercraft has led to the creation of a new branch of technology,
involving the marriage of hydrodynamic and aerodynamic design and production
principles. Despite the rapid pace of development, hovercraft are still in their infancy,
especially for the larger vehicles, and much still has to be learned. Progress has been
encouraging, particularly in the field of skirt engineering, and more recently with less
expensive structures and more efficient power units.
Apart from marine hovercraft, equally exciting developments are taking place in
the application of the air cushion principle in the industrial field. Already air cushion
transporters are in commercial use, facilitating the carriage of extremely heavy loads
(up to 200 tons) over weak bridges and road surfaces and smaller loads (up to 9 tons)
over farmland and open country. With the former vehicle, the heavy cost of bridge