T&T: Hull Speed 20% faster and more economical, by new

[Faure, Marin]

>After much research it was discovered the flexible hull frames created
a shallow convex tunnel along the keel timber. This tunnel trapped sea
foam and air bubbles under the hull and effectively reduced hull skin
friction.

It is common knowledge among floatplane pilots that taking off on smooth
or glassy water results in the longest takeoff run because there is so
much drag on the bottom of the floats.  The ideal surface has small
wavelets that introduce air under the floats and let them accelerate
much faster.  There is a product called "Riblets" which was developed
years ago by 3M which can be applied to the underside of airplane floats
to induce a bit of water turbulence and thus air under the floats.  From
what I have been told by pilots who've flown floatplanes fitted with
riblets, they are quite effective.  The upside for a seaplane is that it
reduces the takeoff distance.  The downside is that it increases the
runout distance after landing.  So pilots must be careful not to touch
down so close to a shoreline that they run the risk of running into it
before the plane has come to a stop.

______________________________
C. Marin Faure
GB36-403 "La Perouse"
Bellingham, Washington