A sub hull is a displacement hull like a sail boat. When you reach the
hull speed, it takes a lot more power for every knot you try to gain over
the hull speed. Like going from 5 knots to 6 knots might almost double
the HP required. So unless you have a very long smooth sub or a nuclear
power plant you probably won't go much faster than that. My sub won't go
5 knots. Even with a 75 HP boat trying to pull it, it won't go much
faster than that. I don't know what I would do with all that speed, pull
a skier maybe. I think 5 anything is way to fast to get a good view of
the bottom, unless you have 50'+ vis and you are in a hurry to get someplace.
Ever try to stop a 5000 lb boat from hitting the dock when it is just coasting
in slow. Now imagine you are moving along the bottom at 5 knots and you
see something you want to take a close look at. ALL STOP!!! ALL REVERSE!!!
WOAH THERE!!! STOP ALREADY!!! oops I missed it. Now you turn the sub around
only to find a huge cloud of silt blocking out all the light. Well that
is what it is like in the small inland lakes around me.
That's my 2 cents worth for the day.
Jon Shawl
Gregory Snyder wrote:
Hey Guys - Hope this isn't too stupid, but how fast is a knot? I downloaded the specs on the US SUBMARINES NOMAD model and it says that it will travel 3.3 hours submerged at 5 knots. That is the same speed that the little ambient SportSub is supposed to be able to travel. That seems somewhat slow for a Million + dollar vehicle. Is this normal for a sub? Is it "fast enough" when you are actually underwater, or is the NOMAD all show and no substance? Thanks, Greg