The Future Above Potter

[TheQ]

21 hours ago, MauriceMynah said:

Very approximately speaking, what is the draft of a traditional broads sailing boat? or indeed a Norfolk wherry, Albion say? How does that compare with a single keeled Westerly or a Pegasus?

We read much about people buying the wrong sort of cruiser for the broads, would it be so unreasonable to suggest there might be unsuitable yachts?

Traditional Broads boats were running agound in the centre of Heigham sound channel before they dredged it.

 Most of the Pegasuses Pegasusi? on the broads are Bilge keel and Draw 3ft 1 inch.. As for westerlies,  there are about 60 different boats from Westerly, but, up to 30ft a bilge keeler would be OK. Some of the smaller boats up to 25ft would be around 4ft draft fin keel, OK on the main rivers but you'ld have to be careful elsewhere.

I know I've had a "discussion" with a motor boat(private) that wouldn't keep to the bank.. He said he drew 2ft 6 inches. I tried to explain his 2ft 6 inches in the centre of his boat, that would be  6ft off the bank where as our dinghies and keel boats were racing with 3ft hanging beneath only 3 ft off the bank..

[JennyMorgan]

An unsuitable sailing boat for the Broads would be, in my opinion, be one with a mast that is not in a tabernacle and is not easily lowerable. Next on my list of wouldn't haves are bilge keels, notoriously bad at tacking in rivers plus, if you run aground, if you try heeling the boat in order to reduce the draft you actually increase it! Anything over 4' draft will be disadvantaged.  

[maysailor]

We draw 4' and we went hard aground on Heigham Sound whilst participating in the 2012 TRR we were not able to get off without using the engine and disqualifying ourselves but since the dredging we have not had a problem there or in getting up to Horsey. We transit most of the Broads network and the only No Go areas in the main Broads network for us are Catfield Dyke, Coltishall to  Horstead Lock and West Somerton. It gets a bit interesting on the upper Ant  to Dilham and at Gelderston.

When sailing you get to know where the shallow areas are but occasionally you hit something you are not expecting

[TheQ]

I probably passed you, as you were stuck there, we were in a Yeoman that year..

I've done the 3 rivers race in a bilge keel Lysander 17ft  many times, only twice not getting round and one of those was with a broken tabernacle.

The maximum handicap they'll give you on 3RR is 25% off your finishing time, a Lysanders true handicap is 35% off the finishing time.  On true handicap one year I would have finished 16th.

Sailing a bilge keeler  can be quite very enjoyable, and if you go agound with a blige keeler it's almost always the bank side keel  and heeling toward the middle of the river will normally clear it..

That being said there is something to be said for an hydrodynamic swing keel, you can have 5ft draft in the deep stuff and just lift it a bit if it gets shallow.

[JennyMorgan]

Many years ago I brought a Silhouette bilge keeler round from Chichester to the Broads, remarkably seaworthy and she handled well enough, albeit slowly. Couldn't swivel her round like a c/b dinghy, either at sea nor on the Broads, but that was no real problem when tacking at sea where once an hour is quite a lot! Where I did find the Silhouette lacking , and various other 'sea' boats, and my Drascombe,  was that none of them held the bank at the end of a tack like a Broads keel boat can. A good friend of mine had a Lysander and he loved it, that was about thirty years ago. He didn't ever race it that I know of but we did have some excellent pub crawls even if he did miss the first couple of rounds!! 

[marshman]

Aha....!   The art of a good Broads sailor - knowing how long to hold the bank after a tack and as a result, making real progress especially into the tide!!

[JennyMorgan]

3 hours ago, marshman said:

Aha....!   The art of a good Broads sailor - knowing how long to hold the bank after a tack and as a result, making real progress especially into the tide!!

Perhaps a really good Broads sailor, at least down South, would also work the tides, especially in a Wherry! 

[Ray]

10 hours ago, TheQ said:

I probably passed you, as you were stuck there, we were in a Yeoman that year..

I've done the 3 rivers race in a bilge keel Lysander 17ft  many times, only twice not getting round and one of those was with a broken tabernacle.

The maximum handicap they'll give you on 3RR is 25% off your finishing time, a Lysanders true handicap is 35% off the finishing time.  On true handicap one year I would have finished 16th.

Sailing a bilge keeler  can be quite very enjoyable, and if you go agound with a blige keeler it's almost always the bank side keel  and heeling toward the middle of the river will normally clear it..

That being said there is something to be said for an hydrodynamic swing keel, you can have 5ft draft in the deep stuff and just lift it a bit if it gets shallow.

I would be interested if the bits I've highlighted could be explained in layman's terms. I doubt I'll ever sail but I often find myself watching yachts with admiration from the helm of my stinky!

[JennyMorgan]

27 minutes ago, Ray said:

I would be interested if the bits I've highlighted could be explained in layman's terms. I doubt I'll ever sail but I often find myself watching yachts with admiration from the helm of my stinky!

For a kickoff bilge keels are these:

[TheQ]

A fixed keel on most broads boats looks something like this.. note Broad boats "fin Keels " tend to be longer fore and aft and shorter vertically due the the need to keep them less than about 3ft 6 inches.

 

[Ray]

Not what I imagined at all! 

Thanks JM

[Ray]

2 minutes ago, TheQ said:

A fixed keel on most broads boats looks something like this.. note Broad boats "fin Keels " tend to be longer fore and aft and shorter vertically due the the need to keep them less than about 3ft 6 inches.

 

That's interesting because it never occurred to me that there would be different designs for different waterways!

[TheQ]

Here is one version of a swing keel, they have the advantage if you hit something they swing up without damage.

[TheQ]

Here is an image of a modern drop keel, totally unsuitable for the broads too deep and weed would catch round the bulb .

[Ray]

That seems a good design, makes sense and I can see the problem with the drop keel!

[TheQ]

Dinghies often have a drop keel but without the bulb on the bottom. as they are proportionately smaller and can lift their keel easily to remove weed or clear and obstruction.

Hydrodynamics, they should be like a double sided Aircraft wing, as aircraft have wings hold you up, where  boat keels produce forward motion against water on both tacks.

 these are from an explanation on keel  shapes for dinghy drop keels  1 being the worst  shape, 4 being the best of those shown.

 

[TheQ]

But ideally you realy want something a lot smoother like these,, the numbers being the National Advisory Committee for Aeronautics (American ) who ran lots of aero dynamic tests to produce the best shapes. NACA  0012 being the general use best shape for boats according to most authorities. 12 being 12% thick compare to the fore and aft length. The top one  on this drawing being NACA 10

[Ray]

I had a feeling this would be an interesting subject... especially to the uninitiated like me. Thanks again 

[TheQ]

A keel resists in the water side ways push of the  air against the sails . I won't go further than that as the maths of it are frightening to me..

Note you almost never sail with the sails dead on the centre line, just with the back end of the sail out away from the wind a little. Getting that angle right gives you the forward propulsion when close hauled. "CLOSE HAULED" with the sail as near to the centre of the boat as possible while still sailing forward..

This is the most used position of sails on a river when sailing into the wind, If the wind is straight down the river towards you. You gradually get pushed towards one bank as you go forward. This is where the skill comes in.

Getting the angle of the sail, and the boat right for best progress against the wind.

If you hold on to that too long, you either end up stalling the boat with the sail flapping about over fore and aft, because you've tried to avoid hitting the bank with boat side or keel depending on depth. OR you hit the bank. both of which may cause damage but will stop your forward progression.

A good sailer will judge it correctly  and tack (TACK= wind passing through dead ahead to the other side of the boat) just before either stalling or hitting the bank occurs. At this point you confuse the mafi's by crossing the river in front of them..and then you do the same when you get to the other side of the river.

If the wind is not dead ahead, then the mainsail can be further out allowing you to sail straight down the river, however you are continually adjusting the sail and rudder to maintain speed as the Wind angle changes, as the river bends and to avoid other boats who may have  right of way over you.

You may have to Gybe, Gybe is the wind changing from one side to the other  across the back of the boat as you change direction. This can be quite hair raising , as the boom may swing violently from one side to the other with a crash..don't get  your head in the way of it occuring..

And finally. now I've bored you to tears, may I suggest coming to our Next open day at Horning Sailing club which will be early May next year, probably in conjunction with the Horning Boat Show. The club will take you out for free, on an experience sail of half an hour ish up and down the river..

 

 

[MauriceMynah]

1 hour ago, TheQ said:

 

 

Ooooh look...                                                                     ... A "Bow and arrow"   ^

[TheQ]

8 minutes ago, MauriceMynah said:

Ooooh look...                                                                     ... A "Bow and arrow"   ^

We need a GROAN button...

[Ray]

I enjoyed reading that very much and will indeed come along next May! 

[Meantime]

1 hour ago, MauriceMynah said:

Ooooh look...                                                                     ... A "Bow and arrow"   ^

Me thinks someone has spent to much time watching Catch Phrase on telly. Well spotted though!

[grendel]

just remember to stick your registration number within 2m of the bow

[TheQ]

1 hour ago, grendel said:

just remember to stick your registration number within 2m of the bow

I could do that on the base of the keel on my mini sailiing keelboat...