Originally Posted by
phillnjack
Ahhh yes, i agree with the testing
but theory when given figures can only be right in the maximum possible.
to get to that figure is where the testing comes into play.
all the testing in the world cannot get you past the maximum possible attainable speed. !!!! the testing is trying to get as close as possible to this speed is what its all about.
we all like to think our boats and cars are farster than they are, ive raced car down the drag strip years ago.
and the amount of times i beat cars that were supposed to be sub 9 second cars was unbelievable.
I never got to maximum theory, neither did donald cambell, neither has anyone who has broken the
landspeed record or air speed record.
No boat has ever gone past or even too its maximum mathematical speed, !!! this is due to many factors.
the boat being the main factor in this case, the absolute perfect boat with zero drag/slip has yet to be invented.
there is no boat anywhere in the world that dont have a certain amount of drag.
And there has not yet been a propeller invented that is 100% perfect, they all have a certain amount of slip and drag to them.
but given a set if figures like revolutions per minute, and a gear ratio and a given size propeller, there is a
maximum speed, there is not getting around it with testing and raising the engine, lowering the the engine or filling
the boat up with helium,the max speed is max speed and that is the target, it cannot possibly be passed.
now anyone who thinks there boat is faster than the maximum calculated speed given the figures of rpm's, gear ratio, and prop pitch is a fool who is lying to himself.
and he is not fooling anyone.
at the top i gave figures, the figures are easy to calculate or to use on a formular, the speed reached can never ever possibly be faster....its just a fact.
test as much as you like with a gps, but dont take ya gps as gosple, no world records rely on gps they use a set length
and a timer, its far more accurate than gps.
with gps you are relying on the satelites , gps is great for pin pointing, but even then not 100%.
gps is a signal sent from a device to a set of satelites and then bounced back, this again takes time.
but in this particular case, the gps is way off target by around 20%.... or the figures quoted of pitch,rpm and gear ratio.
the gear ratio is not suspect in this case as its not going to be different.
33mph with a very good tail wind (hurricane strength) COULD be possible on a race boat.
but what a boat that would be
phill
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