Hamilton Jet HJ241, Manual

Page: 39 / 202

3.5
3 DESIGN BASICS
3.2 H
ULL
D
ESIGN
HJ-241 / HSRX
3.2.3 Multi Hulled Vessel
Jet Units may be fitted in catamaran and some
trimaran hulls. Air entrainment between the hulls
occurs with these vessels and care must be taken to
ensure that this entrained air does not enter the Jet
Unit intakes(s). This is alleviated if the hulls are
deep in relation to the air tunnels so that the Jet
Units sit well down in the water, as indicated in
Fig-
ure 12: Hull Design Recommendations for Multi Hull
Vessel
below. The Reverse Duct when in the "up"
(ahead) position must not project beyond the
sidewalls of a catamaran or trimaran hull, or
substantial drag may be caused.
Consult with C.W.F. Hamilton & Co. Ltd in all cases
if Jet Units are proposed in these types of Hull.
Figure 11: Installation for Multiple Jets
AT ALL DEADRISE ANGLES
JETS MOUNT FLAT TO HULL
MINIMUM JET CENTERS
AT TRANSOM
"B"
"A" "A"
Figure 12: Hull Design Recommendations for Multi Hull Vessel