Prop Guard® is made to surround the propeller like a
nozzle. This designed nozzle action
moves water with a controlled directional force which gives the boat improved
handling and more power. This nozzle
action is accomplished with no moving parts to adjust or replace. Whether you have an outboard or stern
drive, Prop Guard® will increase propeller efficiency, decrease fuel consumption
and improve boat handling while reducing hull and engine stress. Technical testing of the Prop Guard® has proven that the performance of pleasure
crafts are actually enhanced by the installation of the Prop Guard® .
Optimum
performance of any vessel is dependent upon the design match between the type
of engine, its propulsion system and the type of hull. The delicate balance can easily be upset
with an under powered or over powered engine.
Even a perfectly well designed propeller may perform miserably if that
propeller is placed behind an oversized or overloaded hull. Any problem with these elements can result
in poor performance and handling for a vessel.
However, with
Prop Guard® , even with a technically unbalanced craft can increase the
thrust of the propeller. The loss of
kinetic energy due to rotational flow in the water downstream of the propeller
can be partially recovered by the guide vanes of the Prop Guard® as it creates a counter rotation vortex,
reducing the torque effect of the rotating propeller. The hydrofoil nozzle configuration the Prop
Guard® creates forward
thrust, which overcomes its own drag and also provides an effective trim
without drag. Nozzle propellers
produce more thrust than open propellers as the nozzle produces greater
dynamic lift for the boat and permits it to achieve faster acceleration and
planing.
Prop Guard® eliminates the need for existing or
additional drag producing trim devices.
In a steep turn, boats tend to turn on their center of gravity and the
propeller loses its bite in the water creating uncontrolled rev-ups, as the
stern of a boat and the prop moves tangential to the center of gravity of the
boat. This is eliminated as the
greater lateral area of the nozzle produces a larger effective rudder
area. Prop Guard® increases the thrust significantly to
overcome handling problems.
In tests,
vessels with Prop Guard® installed were put
through tight figure 8 turns. The
handling characteristics were greatly improved, as greater lateral area of the
nozzle produces a larger effective rudder area. There is significantly greater steering control at high speeds,
when the vessel made 360 degree turns in 30 to 40 feet compared to 60 to 80
feet with an unguarded propeller. The
stopping ability of the boat is also dramatically increased as the nozzle
presents a greater blockage area.
PROP GUARD® PROFILE
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