Speed Limiting Drogue
A speed-limiting Drogue is towed off the stern. It's purpose
is to (a) limit the boat's speed, (b) reduce her angle of
yaw and (c) to provide for steering assist in strong following
seas. You can, and may have to, steer the boat with the Drogue
in tow. There is a "Catch 22" with any speed limiting
Drogue: The same low pull that allows for steering control
may also allow the boat to broach, capsize and/or pitchpole
in the heaviest seas. The forces that pitchpole yachts are
formidable enough to yank the Drogue through the water in
the course of throwing the boat end-over-end. Sailors should
be aware of this "Catch 22" and make allowances
for it in the course of their decisions at sea.
WARNING: In all likelihood the insufficient drag of
a speed-limiting Drogue will not prevent pitchpole in the
heaviest storms, especially those packing ESW's (Extreme Storm
Waves), rogues and "Three Sisters" type developments.
Design & Construction
The PARA-TECH DELTA Drogue uses the "guide surface
principle". The design is a triangular "Delta"
shape that provides strong uniform flow separation at all
leading edges. Shape retention is achieved by the pressure
of the water inside (similar to the "Ballute" drogues
used in aerospace applications). The relatively small mouth
at the leading edge makes it extremely unlikely that one will
get turned inside out (a problem associated with large cones
and small parachute drogues). Also, the three ears of the
DELTA Drogue have the effect of increasing the Drogue's drag
as speed increases.
The PARA-TECH DELTA Drogue is extremely SIMPLE in
design and construction. So simple that it is made from heavy
duty vinyl coated material