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Old 24 August 2004, 11:51   #1
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Open Transom versus Closed Transom

I don’t understand why more inboard engined ribs don’t have open transoms.

As I see it, after a big stuff with the boat full of water, an open transom allows the boat to drain without the need to do anything, whereas with a closed transom you have to power the boat forwards to get the elephants trunks to work. This can be a difficult situation because with a ton of water on board the boat might not be handling at its best and you could find that the next wave catches you as well.
I know that to get an open transom the rib designer has to set the deck at a height level with the water and in smaller ribs this is not practical, but in larger ribs it could be, yet Halmatic and one or two other commercial manufactures seem to be the only ones to do this.

Another advantage is that getting in and out of the boat is easy, a full kitted diver can get himself out of the water without help over a low transom but needs help coming in over the side.

Open transom are increasing common on sailing yachts and dinghies but not on ribs why.

Des
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Old 24 August 2004, 12:04   #2
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Firstly Des, I don't realy know why........but here are my toughts anyhow.

Sailing boats do not generally have gert great wakes following them around, and the don't tend to alter speed suddenly. I know every time I slow down, the wake tries to climb in over the transom. If it was not there all my sarnies, beer, cold box, discarded clothing, kids etc would get washed out of the back as the water rushed back out. Maybe a transom with a "garden gate" like gin palaces may be the answer to your boarding needs.
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Old 24 August 2004, 12:08   #3
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Atlantic 21s have em don't they? good idea for applications like that and other foul weather/commercial things I guess.

However, for the leisure market, I reckon people don't want to buy a RIB with a hole in the back! With an open transom the boat will probably have a permanently wet deck (especially when reversing!) and with a higher deck a certain feeling of security may be lost (sitting on, rather than in the boat).

I can't really think of much of a reason why more commercial RIBs don't have open transoms.

Tim
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Old 24 August 2004, 12:39   #4
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Quote:
Originally Posted by Mark Halliday
Firstly Des, I don't realy know why........but here are my toughts anyhow.

Sailing boats do not generally have gert great wakes following them around, and the don't tend to alter speed suddenly. I know every time I slow down, the wake tries to climb in over the transom. If it was not there all my sarnies, beer, cold box, discarded clothing, kids etc would get washed out of the back as the water rushed back out. Maybe a transom with a "garden gate" like gin palaces may be the answer to your boarding needs.
I know what you are saying , but with my boat(open transom hence the interest) never gets the wake in over the back, what tends to happen is the back just lifts when the wake comes close. Although my beer is wet it never gets wet Different hull shape I don’t know.

Des
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Old 24 August 2004, 12:41   #5
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Quote:
Originally Posted by slimtim
............especially when reversing!.............

Tim

you are right about reversing, water all over the place
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Old 24 August 2004, 12:55   #6
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Des

I must have a closer look at a Pac22. The only 1 I know of is Mr. 7s and alegedly you cant see the transom for smoke, and when the smoke clears it is going too fast....
Any chance of a picci?

P.S. Do Millets still do anoracks? I might need one soon.
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Old 24 August 2004, 13:08   #7
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Quote:
Originally Posted by Mark Halliday
Des

I must have a closer look at a Pac22. The only 1 I know of is Mr. 7s and alegedly you cant see the transom for smoke, and when the smoke clears it is going too fast....
Any chance of a picci?

P.S. Do Millets still do anoracks? I might need one soon.
Not a great photo but you can see the water line or at least the antifouling line. The height is about 6 to 8 inches ish.

Don’t worry about the anorak I have a spare you can borrow , a very nice 1972 Millets style parker with real fake rabbit fur.
Des
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Old 24 August 2004, 14:17   #8
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I see now, you have a low transom, not totally open like below.

Quote:
Originally Posted by Scary Des
Don’t worry about the anorak I have a spare you can borrow , a very nice 1972 Millets style parker with real fake rabbit fur.
Des
Nice offer by I was brought up in the contryside and I am allergic to fake real fur. Has to be the real thing, preferably still warm.
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Old 24 August 2004, 16:26   #9
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Des
I think you will find that a lot of boats have a full transom because it makes it easier to build a stronger hull if its there.
The ribs I have seen without transoms have normally been higher end of the market hulls which are so dam strong any way or are ali.

Jelly
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