bridgedeck clearance

PDQ issues applicable across all PDQ Yachts (or if you can't find a place for something, it probably belongs here for now)
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joe
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bridgedeck clearance

Post by joe »

I was wondering what the "average" bridgebeck clearance is i`ve heard this is an issue on cats we are trying to get info on seaworthy cats an pdq`s appear to fit that discription
Allezcat
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Re: bridgedeck clearance

Post by Allezcat »

Joe,

My opinion only!
You will get many opinions on bridgedeck clearance. Some say the more the better but I'm not convinced. I have an early PDQ36, the first one actually. Looking under the boat, the clearance is very low, maybe 10 to12" under the lowest part ( the athwartship companionway). On later boats they raised this about 4" but then also raised the cabin roof 4" to get "more clearance". They, (all cats I have been on), pound from waves hitting the underside when going to weather, mine included. This does not seem to hurt the boat structurally but does slow it down and make for a rather uncomfortable motion in big seas compared to a keelboat. I think to eliminate this would take bridgedeck clearances far in excess of anything I've seen on the market and would probably have astronomical windage. I actually like the low clearance because it acts like a "planing surface" when going downwind,(my kind of sailing), like sledding downhill on the waves. So for ocean sailing I prefer a keelboat but for fast coastal sailing and shallow waters (like the Bahamas) I love the catamaran!

Chet
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thinwater
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The PDQ 32 is actually a little different.

Post by thinwater »

The clearance is a bit greater, enough I can get my inflatable under with some clearance, and the beam is a few feet less. The result is it is difficutl to get it to pound, unless the chop is very steep and close indeed. Even then, it is only every few minutes and not strong. In the ocean I never strike, only in certain bays.

It may also depend on load, but my comments were based on a full coastal cruiseing load for a 2-week trip.

Actually, there is a vidio of my boat banging into 20 knots on the mid Chesapeake Bay, taken from underneith! you are not the frst to ask. The link is on the rightside of my web site.
Writing full time since 2014.
"Rigging Modern Anchors,"Seaworthy Press, https://www.amazon.com/Rigging-Modern-A ... 1948494078
Book Store. http://sail-delmarva.blogspot.com/2017/ ... store.html
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maxicrom
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Re: bridgedeck clearance

Post by maxicrom »

Joe,

I have to agree with Chet, we also have a PDQ 36 which is our first catamaran. On our maiden sail we left Worton Creek near Chester on Chesapeake Bay heading south to the Potomac river and 5 hrs out the weather turned with small craft warnings and the wind topping 25 kts on our nose (it was in December). We headed into Galesville, the next day tried again and only made Herring Bay before it got too rough - being a new boat to us and not sure of all the systems we choose to err on the side of safety. Finally we got a weather window (wind dropped to 10 - 15 kts still on our nose) so we pounded down the bay for 10 hrs, slop was about 5 ft. so the boat would launch off the 1st wave, coast into the next, body slamming the 3rd - we tried a number of options and this seemed to be the most efficient method (and if you can believe comfortable). It really took some time before we saw that the boat was doing fine with it (much better than ourr dogs). Feeling the hit and seeing the mast shudder on our "new" boat was still a little un-nerving. After talking to other cat owners we learned that this is common with cats, plus the bay can get a fairly steep chop going.

Another option to consider might be a tri-maran, I used to sail on a 40' Tri out of San Francisco and we did some coastal trips. With a cruising tri you pretty much give up the option of a slip (because of the width) but do get a better offshore ride. It's my opinion that a Trimaran in sloppy seas has a more violent snap motion but the center hull resolves the belly flop you get with a cat.

Good luck with your search,

8) Mike
Mike & Linda
S/V II the Max
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