How fast can a Top Hat go?

[8philip8]

hi Mark
"Sylph" mkIII do have water come in from the drains with 3 people in the cockpit over 5knots ,even on motor power.
so the cockpit floor should be higher then it is .
8philip8

[rob.lovelace]

I've been waiting for this string. Mk3 outboard in well. 6-7 kts in a stiff breeze well heeled water comes in the cockpit from the well. It also runs to the front of the cockpit in the gutters when boat is still like it doesn't have enough fall to the stern. I was thinking this was because I have no heavy inboard diesel in her. As for top speed I can often get 7kts in the conditions you mention. I'm thinking of blanking in the outboard well and using it for a stern anchor locker. What is the hull speed anyway? 5 to 6 kts ??? She goes much faster that's for sure Bass Stait in 30+ got he moving last Christmas

[storm petrel]

G'day Rob,

With a waterline of 21 ft, the hull speed of a Top Hat would be 6.1 knots using the standard formula of 1.34 x SQRT (waterline length in ft). Going downwind/heeled with the stern tucked down the water line length might increase to 22-23 ft and the hull speed would accordingly lift to about 6.3 - 6.4 knots.

S and S 34's have a hull speed of 6.6 knots, but can reach 7.5 knots even in a moderate breeze and when pushed hard downwind can exceed 8 knots, so exceeding 7 knots in a Top Hat should not come as a surprise.

Interesting to hear that you also get water entering the cockpit when travelling above the hull speed. If I reduce sail on Storm Petrel and keep her a little more upright which limits the speed to about 6 knots I do not have the problem. I guess it is not that much of a problem and I really only noticed it when my wife pointed it out and started to tell me the boat was sinking! So naturally, I notice it all the time now. 'Not dangerous', as I reassured my wife, 'just annoying', but with wet feet she was hard to convince.

Does your cockpit drain through the outboard well or do you have separate drains?

Cheers,
Mark

[bearmcnally]

BOY DON'T YOU NON MK1 OWNERS HAVE PROBLEMS ?

[rob.lovelace]

Mine drains into the outboard well Mark and thats where it comes in

[Tales]

In Port Phillip Bay we get a nasty short chop and hard on the wind or on a fine reach a lot of water can come up through the well (MK III/outboard).
The odd wave will wash straight up and lay in the lee seat/coaming until we tack.

Have not had the problem in Bass Straight that I recall but in 30+ knots outside the Rip, we had other things to think about!

We just lift our feet or wear sea boots in Winter.

Tom

[Dolphin]

Bear,
everyone knows that MkIIIs are faster than MkIs. Shaun has video proof of Felicite on lake Mac.
MkIs are so slow the filter feeders catch up to the prop, weigh it down and snap the shaft! That's my theory.

As a guide, on Felicite, the marline board, or the wood that it was hinged on usually becomes covered with water when she is powered up. See the pic below. When that happens the water laps at the rudder stock

[attachment=0]P1020827a.jpg[/attachment

Greg.

[bearmcnally]

Mr Greg ,

This video you talk about ? what are you sailing against ?

Bear

[SeaLady]

So when the water comes into the cockpit you are going faster than the hull speed?

Is that what it means?

Woo Hoo

I do that all the time when on a reach or goosewinging.

I must be a fast girl.
And I tell people I am built for comfort not for speed.