Page 33 - Theory and Design of Air Cushion Craft

18 Introduction to hovercraft

Fig. 1.18 Hovermarine HM-221 SES fireboat on trials before delivery to port of Tacoma.

other transport systems such as hydrofoils, high-speed monohull passenger craft, high
speed catamarans and long range buses and trains where appropriate. During the
1970s many companies had been set up in the UK and USA to develop business in
constructing ACVs of all sizes from 2 seat recreation craft to large ferries. Many of
these companies did not exist very long, often producing little more than design pro-
posals. Those that were active found marketing difficult, as the public found the con-
cept intriguing, and more of a 'solution looking for a problem'. Trial passenger
services gained a reputation for unreliability, and short lived operation. Only the
established services across the Solent and the Channel proved viable in the long term.
This situation did not support the planned development of larger hoverferries. On
the other hand, Hovermarine developed the right 'formula' with their sidewall ferries,
which demonstrated reliability and demonstrable economy at higher speeds than
available displacement ferries. A tunnel was planned across the English Channel, and
construction began in the mid 1980s, which lessened the need for an SR.N4 replace-
ment. At other places, such as Hong Kong to the delta area of the Pearl river, the sit-
uation for SES transport market developed rapidly, supplied by Hovermarine Ltd.
Following the initial phase of entrepreneurs establishing companies to build hover-
craft, those which survived were those who were able to supply practical vehicles to
customers who were mostly in remote areas, on the other side of the world. This is a
tall order for a small enterprise, though an essential one for a craft such as the ACV.
The use of local representatives is one way forward, though this can also be difficult,
since unless the local representative is competent - difficult with a new vehicle concept
- then the client will once again become frustrated that the ACV appears not to per-
form as expected. Expectation by the clients matured over the 1980s, as craft them-
selves became more reliable, and to some extent 'under-sold' by the manufacturers.
While the initially expected expansion of an ACV ferry market did not materialise,
due to their limited open sea capability, the utility market for craft with payloads from
10 tonnes downwards developed steadily. This is the core application for ACVs. In the
UK, Hovermarine developed a second generation of thin sidewall SES, the 250 seat