Why aren't flooding keels popular in WA?

Chivers were doing them but no longer making ally boats.

Westerberg do on some (westerberg Eclipse), but not clear on website.

Sherwood Marine has designs but only sell the design.

In NZ oviously they are popular (Bar Crusher, Extreme etc), also Svensson in Qld doing them and Noble used to do them.


I don't see any major drawbacks to floodable keels, allows for a deeper Vee, smaller chines and better stability at rest. Sure slightly more draft at low speeds.


From what I can see pretty much all the ally boat builders use use the Jackman or Dennis Walsh design which really hasn't changed much in the last 30 years. Is this because of cost, they have the templates already and just keep on usng them, modifying them at no cost / effort.



quadfisher's picture

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Down the gurgular??

Fri, 2021-11-05 16:08

 Cause the word flooding and boats should never be mixed in togeather!

 But its deff not a new thing , a mate had a glass boat from the late 70,s or 80,s and it had one ,, it did take a far bit of throttle to get it up 

 on the plane tho ,, and id imagine it adds complexity to below deck designs what with plumbing , fuel tanks , bouyancy foam / chambers etc etc

 New ideas and designs sometimes work well but for whatever reason just dont find favor and we all just move on ,,, think stable tables , airless 4wd tyres, chrome spoon lures  

 or fishing rods with line thru the blank ,,,,, and who could forget sleeved wearable blankkies haha...



rob90's picture

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Might upset the surtees boys

Fri, 2021-11-05 16:15

Might upset the surtees boys calling bar crushers NZ boats. But yes good concept just extra wank factor really imo


 Hi my name is rob............. and I'm a........... fishaholic

Percula's picture

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Fri, 2021-11-05 19:37

 I didn't know chivers stopped making boats. Is this old news?


Swompa's picture

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 I thought they still did the

Fri, 2021-11-05 19:39

 I thought they still did the Shark series...

VaSSagO's picture

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Can only see Surtees &

Mon, 2021-11-08 09:27

Can only see Surtees & Stessco on their website under new boats.

Swompa's picture

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 My my former brother in law

Fri, 2021-11-05 19:41

 My my former brother in law (sort of) had a boat with a flooded keel/kill tank (that was designed to flood when at rest and empty when underway). It used to slop with water splashing up. Through the deck seal. 

wasn't great.

Saulty2's picture

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floodable keels

Sat, 2021-11-06 07:26

 are a joke , unstable on a drift . try beach launching in shallow water ! and see what happens,  local builder that no longer fabricates has seen the light & lost money on them , mine was  6.3m true length ..... boat went back to their yard some 30 times , because of the configuration not enough space between petrol tank  & hull  major problems , could go on but enough to say {lemon } 

Bucko's picture

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 Saulty, Pretty sure I have

Tue, 2021-11-09 13:19



Pretty sure I have the same boat your talking about.


Whats the issue with the fuel tanks?



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 Sea Devil (glass) have the

Sun, 2021-11-07 08:24

 Sea Devil (glass) have the flooding keel, but flooding keel boats are a PITA to beach launch or beach as they are awful to try and get off the sand. Mechanically floodable ballast tanks are a better way to go imho.



VaSSagO's picture

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Yeah I was thinking the Bar

Mon, 2021-11-08 09:34

Yeah I was thinking the Bar Crusher type with the mechanical flap  which can prevent water getting in or hold it in.

Current boat has a kill tank and yes agree with the comments re water slapping (in addition it drains too slowly).


Appears the tried & tested Jackman design is what the populus wants. That answers my question

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 I reckon the major designer

Tue, 2021-11-09 14:07

 I reckon the major designer of aluminium recreational boats in WA is probably Bill Plug?

Assassin, Oceanic, Redline and a few others use his designs almost exclusively.

I'm not sure how many interstate builders use him but here he is big with a low profile-my hull is number #239 from memory.

Floodable keels-is a great idea esp[ecially with a flap to keep it in-avoids having a tender hull when fuel is near empty on a deep V.

Scaling up though the effect is less prominent.


 Give a man a mask, and he'll show you his true face...



The older you get the more you realize that no one has a f++king clue what they're doing.

Everyone's just winging it.


Saulty2's picture

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my experience is

Wed, 2021-11-10 07:03

 floodable keels reduces the hull space , petrol tank then is too close to the base leads to pitted hull with major work to rectify  ,beach launching in shallow water has issues like if it digs in with some sand then your in for major issues , it has happened to me , mine did not have a flap but cant see that the flap would be any different than to fill both kill tanks .IMO just another marketing tool  

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 The idea of the flap was to

Wed, 2021-11-10 08:33

 The idea of the flap was to keep the water in the hull to help the ride in rough water. No flap the water just runs straight back out. 

I know some of the older Smuggler hulls ran a flooding keel. Now that fury has a set of Smuggler moulds it will be interesting to see if they run them in their Fuggler. 


Does anyone know where the love of god goes, when the waves turn the minutes to hours?

pelagicyachts's picture

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Hydrofields used to have them

Wed, 2021-11-10 08:12

Hydrofields used to have them in the centre hull (which was stepped) - they had a sealed cavity that went from the back of the step in the centre hull (just back from midships - like the Catalina flying boats) right up to the bowsprit base- the bow had two air intakes below the bowsprit which fed into this cavity which meant when you drove off the keel would empty quickly and would also serve to reduce the low pressure caused by the step which would make the hull more efficient -

so there