Parallax wrote:

Does towing my hard shell dinghy effecively increase my waterline
length thereby increasing my hull speed?


no

Could you add a lightweight inflatable extension to the waterline of a
boat to increase its waterline length thereby increasing its hull
speed?


probably not, as it has to support the boat. What you're describing
would probably just deform and not change your effective LWL. Its drag
would probably erase any benefits.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
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