What is the Smallest Boat That You Would Sail Outside of Coastal Waters?

[rtbates]

Originally Posted by goboatingnow

Broad beams are more resistant to capsize, they have a greater moment of inertia. What can be a problem is when they capsize they are too stable upside down. It's a trade off. Long keels and narrow beams are not inherently more seaworthy just different.

Dave

I believe you are in-correct...

[thomm225]

Here is a list of boats that has completed the Singlehanded Transpac Race (SHTP). The race is from San Francisco to Hawaii. All the boats are not small, but there are a few in the 20-28' range. The 3rd place boat in 2012 was a Pearson Triton 28 I do believe. There was also a Moore 24 in the 2012 race. Click link below:

http://sfbaysss.org/TransPac/transpa..._1978-2008.pdf

2012 results: http://yb.tl/Leaderboard/shtranspac2...+start%27+mode*

2012 boats and skippers: http://singlehandedtranspac.com/entries/



Tom
Bristol 27

[mrohr]

Re beam/stability: the poster that !st raised the question of beam is probably refering to his MULTIHULL; hence his minimum requirement of 25' beam.

[thomm225]

Originally Posted by thomm225

Here is a list of boats that has completed the Singlehanded Transpac Race (SHTP). The race is from San Francisco to Hawaii. All the boats are not small, but there are a few in the 20-28' range. The 3rd place boat in 2012 was a Pearson Triton 28 I do believe. There was also a Moore 24 in the 2012 race. Click link below:

http://sfbaysss.org/TransPac/transpa..._1978-2008.pdf

2012 results: Leaderboard : Single Handed Transpac 2012*

2012 boats and skippers: Overnight shipping viagra ::: TOP Online Drugstore.

Looks like a Cal 20 completed the race in 19 days..............that's around 2100 miles of open ocean on a 20'boat!

[Andrew Troup]

Originally Posted by carstenb

Andrew


Somewhere, logic (which is not all that logical sometimes in sailing) would indicate that a wider boat would need a bigger wave, and therefore in the "same given sea conditions" wide = more stable" (all that is assuming no skidding )

Yes, lets not talk any more about skidding and tripping. It gets complicated.

Also, lets acknowledge that a dangerous wave which is truly breaking* in deep water is almost certain to be higher than the beam of any yacht most of us will find ourselves in. Or the length, for many of us.

So the point is perhaps an academic one. All these boats will be at risk of capsize.

But that doesn't mean it's not worth considering, because the degree of risk will still vary, so here's my best shot at teasing out one issue at the core of the discussion:

Imagine taking a big (roughly cylindrical) log of wood, and fastening a compactly shaped heavy lead weight under the midsection, at the outboard end of a long spike or strut (narrow to minimise tripping).

Take that log to a nearby surf beach and tow it out (some surf waves are a little bit similar to deep sea breakers - certainly a lot closer than anything you'll find in a wave tank) and leave it side on to the break.

Regardless of wave height, I think you'll find that a small furry animal perched on top will not have to run around the log very much to stay on top, provided their claws are sharp. This is because the narrow log doesn't much care about the angle of the waterplane: the primary drivers for which side is uppermost is gravity acting on the lead, and the principle of conservation of angular momentum (the same thing that keeps the earth spinning, remembering the spin of the vortex of star debris from which it formed all those billions of years ago).

Now (back on earth!) take that same hypothetical log and rip-saw it into planks and fasten them alongside each other to make the same amount of timber into a flat scow shape, as wide as the surf is high.

If you run out of hypothetical timber to reach the required beam, make it a multihull, but with a central crossmember so the same strut and ballast bulb can be fitted as before.

Now that the water can exert considerable leverage or 'purchase' to overcome the righting moment arising from the ballast, the 'boat' will try to conform to the local waterplane on the face of the wave.
This implies rolling through roughly 90 degrees:
In effect 'form stability' has become our enemy, because the water which was once horizontal is now vertical.

In this new orientation the white water crest, detaching and tumbling down the sloping face of the green water, acts predominantly on the underside of the scow near the top of the uphill side, and the prospects of capsize become considerable. Some small furry animals may be harmed.

*(rather than spilling a small amount down the front and most down the back, as 99.99% of what people refer to as "breaking waves" do, in deep water, in the absence of strong currents or upwellings)

[oldragbaggers]

Originally Posted by Andrew Troup

Yes, lets not talk any more about skidding and tripping. It gets complicated.

Also, lets acknowledge that a dangerous wave which is truly breaking* in deep water is almost certain to be higher than the beam of any yacht most of us will find ourselves in. Or the length, for many of us.

So the point is perhaps an academic one. All these boats will be at risk of capsize.

But that doesn't mean it's not worth considering, because the degree of risk will still vary, so here's my best shot at teasing out one issue at the core of the discussion:

Imagine taking a big (roughly cylindrical) log of wood, and fastening a compactly shaped heavy lead weight under the midsection, at the outboard end of a long spike or strut (narrow to minimise tripping).

Take that log to a nearby surf beach and tow it out (some surf waves are a little bit similar to deep sea breakers - certainly a lot closer than anything you'll find in a wave tank) and leave it side on to the break.

Regardless of wave height, I think you'll find that a small furry animal perched on top will not have to run around the log very much to stay on top, provided their claws are sharp. This is because the narrow log doesn't much care about the angle of the waterplane: the primary drivers for which side is uppermost is gravity acting on the lead, and the principle of conservation of angular momentum (the same thing that keeps the earth spinning, remembering the spin of the vortex of star debris from which it formed all those billions of years ago).

Now (back on earth!) take that same hypothetical log and rip-saw it into planks and fasten them alongside each other to make the same amount of timber into a flat scow shape, as wide as the surf is high.

If you run out of hypothetical timber to reach the required beam, make it a multihull, but with a central crossmember so the same strut and ballast bulb can be fitted as before.

Now that the water can exert considerable leverage or 'purchase' to overcome the righting moment arising from the ballast, the 'boat' will try to conform to the local waterplane on the face of the wave.
This implies rolling through roughly 90 degrees:
In effect 'form stability' has become our enemy, because the water which was once horizontal is now vertical.

In this new orientation the white water crest, detaching and tumbling down the sloping face of the green water, acts predominantly on the underside of the scow near the top of the uphill side, and the prospects of capsize become considerable. Some small furry animals may be harmed.

*(rather than spilling a small amount down the front and most down the back, as 99.99% of what people refer to as "breaking waves" do, in deep water, in the absence of strong currents or upwellings)

You lost me at "Yes".....

[thomm225]

Speaking of capsize:

Fatty Goodlander, S/V Wild Card - Heavy Weather*...sometimes the sea gets in a grand mood...

and then there is this. I believe the crew was below working on the engine:

http://www.youtube.com/watch?v=NKusg6Jyc9Y

[thomm225]

And small boats off shore:

http://www.youtube.com/watch?v=FdXxNZcXN3I

[oldragbaggers]

Very eye-opening videos. My husband has described those types of conditions to me from his days of plying the oceans on a Navy ship, but quite something again to see them. Thanks for posting those.

Equations as they apply to "small" boats probably don't really mean a whole lot in the face of those conditions. I should think that what makes a boat safe in that environment is a skipper who took every precaution to avoid being out there in the first place.

[carstenb]

Andrew,

Certainly a breaking wave out in bluewater conditions will be higher than any of our boats are long or wide. (I can't imagine being pitch-poled). Leaving issues of tripping and skidding, let's try to answer becky's concern. In very heavy seas, deploying a drogue or warps (in essence running before the storm with something heavy out behind you to slow you down) is a classic maneuver. The warps/drogue will keep your stern to the waves and unless you run into something really big (pitch pole) you will not end up beam to the waves and therefore will not capsize.

The Pardley approach is to set a sea anchor at a slight angel to the waves and ride it out. I haven't studied the Pardley approach enough to critique it. My inner logic says runs in front of it.

What about you ?

[David_Old_Jersey]

Originally Posted by Andrew Troup

As a rule, I reckon small boats are easier on themselves, and harder on the crew.

I think that pretty much sums up the position .

Not to say of course that all small boats are created equal - some (most?) simply ain't built to withstand serious and prolonged weather, and were never intended to be used that way.

If you are relatively immune to seasickness and adaptable to cramped, wet conditions and heeling, there's a lot to be said for small boats. It's a much more active and interactive way of sailing, challenging and enjoyable, both to a high degree.

I think the key is to enjoy the challenge (or failing that to at least get something out of the experiance beyond simply being a method of getting from A to B under sail).

[MacG]

Sailing with the waves. The long and narrow hull of this yacht could (barely) comply.

Hull design in such a situation is probably the difference between a broach and a capsize.

I would opt for the long, narrow and deep hull. Rather than the today' s design.

[thomm225]

Originally Posted by thomm225

And small boats off shore:

Yes, it definitely has a lot do with experience probably much more so than the boat. That racing boat about 2 minutes in has reefed the main and is using a smaller jib but is still in race mode with the hammer down!

And check out the guy about 1 minute in hanging on to the boom...........looks like he (the crew) may have been through that surf line before.

[barnakiel]

Originally Posted by carstenb

(...) you're saying that the beamy boat will be more prone to capsize than a narrow one (...)

Well, if the beam is more than the breaking waves are tall (say you are sailing a lake), then you are safer (than in a narrower boat). But what if they are not? (say you are sailing an ocean)

E.g. remember that the beamy boat will have her lee deck sunk deeper in the wave - and more bottom area exposed to the rolling water - both factors may contribute to a deeper capsize.

I think, in real life, boats are unlikely to capsize or get rolled 360. When they are, both types (narrow/beamy) will do so equally - the beamy ones then are more prone to stay inverted for longer (some - for ever).

It is far more common however for boats to get badly knocked down (flat, or mast in the water). When sea conditions are bad like this, my personal experience says (along with some reading of accident accounts) that the narrow boats are knocked down more often but they seem to recover better while the beamy ones have fewer but more severe wipe outs.

It is all a long and involved story and can be viewed from so many angles that in the end probably everybody is right. This has been proven in many a thread at CF ... ;-)

Narrow or beamy, make sure that if you are crossing waters where such a wave can exist, your boat is prepared to get wiped out, capsized and rolled 360 - and that she will recover.

Cheers,
b.

[carstenb]

Well Barnikiel, Aren't you just the cheerful one today? LOL

Be prepared to get wiped out - great marketing line if you are selling extreme adventure!

How about getting to the other end of the passage and the worst that happened was spilling my sundowner?