الفهرس 
General IntroductionOnly 14 pages are availabe for public view
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Abstract
The aim of the thesis is to assess the advantages as well as the possibility for the
adoption of the surface effect technology in the design and for conversion of
conventional high speed boats. All characteristics and forces, which act on the planing
hull type and air cushion vehicle (ACV) type, were studied. Also, the lifting force,
thrust and lifting power to generate air cushion under the ACV type were calculated.
A conventional surface effect ship (SES) rides on air cushion, which is contained,
between the twin hulls of a catamaran. To contain the air cushion, flexible skirts are
necessary at bow and stem and these can provide a major maintenance problem. The
flexible skirts are replaced after 500 - 1000 hr or six months of commercial service
and there are excessive losses in the lift power due to the more air leakage between
the bow and f~rward skirts. Recently a new concept based on SES, which requires no skirts, was developed. The concept utilizes a catamaran hull with the air cushions
contained under the two side hulls rather than between them. The new concept
through model tests showed that the resistance when riding on the air cushions was
between 50 percent and 60 percent of that of conventional monohull and catamaran
designs.
A case study of an existing naval unit was carried out to implement the unskirted SES
concept in such a way to reduce the required power at a given speed or to gain higher
speed at the same power. Three different constructional proposals are suggested. The
resistance, propulsive and lifting power are calculated and compared with the
conventional boat performance.
The conversion process resulted in a 45 to 50 % reduction in power and about 60 %
reduction in resistance.