peterchech

Where is the limit on an f27/f28?

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This past weekend, with the new screacher up in about 10-15 knots, we managed to stuff the ama of my f28r. It was dark so we couldn't see it but definitely felt it. It popped up on its own before we had time to ease the sheets, really no big deal even tho gps had us pegged at 18 knots sog right before stuffing. Did not round up or down, the whole boat just seemed to slow down symmetrically.

Its still a new boat to me and i've sailed it less than a dozen times so far. With the kite up we have put the ama under but never really stuffed it to the point of slowing down the boat. At least not yet. In many forum posts, it appears that submerging an ama in big breeze is not uncommon in f27's and f28's. And it seems hard to find examples of f27 or f28 capsizes, especially compared to f24's and f31's. Experienced racers have recommended the f27 and f28, and warned against the f31, for short handing or inexperienced crews partially due to the relative capsize risks (or lack thereof for the f28).

Is an f27 or f28 actually an inherently safe design? Obviously THERE IS A LIMIT but could the design somehow tend to depower automatically when an ama digs in, prior to the acceleration in the mainsail torquing it into a pitchfork?

Or is this just a false impression, should I be depowering way before an ama submerges even when racing? Is the ocassional ama submersion in big air (assume no waves) a sign of having passed the limit, or is that in fact the limit and where you want to be when racing?

 

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While I have only sailed a few fboats my first thought is there is a big difference between 10 knots and 15 knots in terms of getting overpowered.  I have had some experience with the leeward hull of my cat going too deep; but that was not just a function of boat speed but waves as well.  Sailing in the Gulf Stream it is common to encounter what are called square waves if the wind has any North fetch; and often with a very short period.

Point is the sea state as well as the wind speed is a big consideration.  It is easy to say 'assume no waves' but that is probably very uncommon if you are sailing at 18 knots.  I tend to make a lot of vids when sailing my boat and review them to better understand what is happening.  I know you said it was dark and you could not see just what happened but even 15 knots does not seem anywhere close to the limit on a C27/C28 in terms of being overpowered.  As an aside More than once in the ICW when motoring at 5-6 knots even when I turned into the four foot wake of a big sports fisherman going 20+ knots I have had a wave break over my bows.  I have seen multiple posts about reefing a C27/C28 at twenty knots.

Maybe I am wrong about all of this but it sounds to me like you hit a one time wave and were not really overpowered.

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If you say you didn't have time to drive or ease properly...then the limit is you, not the boat.  

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Just now, mundt said:

If you say you didn't have time to drive or ease properly...then the limit is you, not the boat.  

Exactly. Try again with more light, drive it like a skiff, go deep in the gusts, work the AWA, bring all the crew weight as far back and out as possible, etc. Find the limits, find the dynamics.

In chop it'll be harder/riskier, there'll be a "path" to weave through (related to wave length). Certain wave patterns, there might not be a happy path so you will have to pull back.

Many variables at play in a very dynamic system; and one of the most powerful ones is your skill / practice level. 

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2 hours ago, peterchech said:

hard to find examples of f27 or f28 capsizes, especially compared to f24's and f31's. Experienced racers have recommended the f27 and f28, and warned against the f31, for short handing or inexperienced crews partially due to the relative capsize risks (or lack thereof for the f28).

Is an f27 or f28 actually an inherently safe design? Obviously THERE IS A LIMIT but could the design somehow tend to depower automatically when an ama digs in, prior to the acceleration in the mainsail torquing it into a pitchfork?

Or is this just a false impression, should I be depowering way before an ama submerges even when racing? Is the ocassional ama submersion in big air (assume no waves) a sign of having passed the limit, or is that in fact the limit and where you want to be when racing?

 

F27 is a tank.  Fixed mast and (as designed) no bowsprit.  Is very unlikely to capsize or pitchpole.  F24s are hard to capsize (mk 1 and 2). Between 1998 and 2010 there was exactly one capsize and that occurred because of a big roller that lifted the stern (plus a buncha wind).  

However, Corsair designed boats (not Farriers) are a little less safe and more of them so you will get more oopses.  

No need to depower "way before an ama submerges even when racing".   Learn your boat.  Be cautious and don't cleat the spin, screach  or mainsheet in big wnd - be especially cautious in following waves where the wave is half the boat length or bigger.    Head up, travel down going to weather when pressed.  Fall off, sheet out downwind when pressed.  Reaching courses are where you are likely to get into the most trouble since your racing instinct is to just head to the next mark and tiller may not get you out of trouble immediately.  

 

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you can submerge an ama on an F9/F31 without too much drama. They just keep trucking straight on...

Goldfinger RSAYS 2016.jpg

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I had a modified F-27, and the PO was friends with a rockstar who got the boat to 27kt.
 

Me, not being a rockstar, got 21 and change before I chickened. I did not bury, and it was under screacher

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The Farrier 2012 Sailing Manual is a great resource. Check out page 20 for some thoughts on this topic:

It is not unusual to drive the low resistance float bows through waves, or even submerge the float in some circumstances. This has been found to have no adverse effect on the boat, and in fact the boat will tend to round up slightly, not slew to leeward as commonly and mistakenly believed.

Early Farrier designs used low buoyancy floats, and frequently completely submerged the leeward float, with speeds in excess of 15 knots, for quite some time, with no ill effect on the boat. However, this is sailing on the limit, and don't push your luck unless prepared for a ducking.

Sea state is a significant variable in how hard you can push the boat - it's much safer to push hard in flatter water (e.g. offshore breeze).

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16 hours ago, Tomfl said:

While I have only sailed a few fboats my first thought is there is a big difference between 10 knots and 15 knots in terms of getting overpowered.  I have had some experience with the leeward hull of my cat going too deep; but that was not just a function of boat speed but waves as well.  Sailing in the Gulf Stream it is common to encounter what are called square waves if the wind has any North fetch; and often with a very short period.

Point is the sea state as well as the wind speed is a big consideration.  It is easy to say 'assume no waves' but that is probably very uncommon if you are sailing at 18 knots.  I tend to make a lot of vids when sailing my boat and review them to better understand what is happening.  I know you said it was dark and you could not see just what happened but even 15 knots does not seem anywhere close to the limit on a C27/C28 in terms of being overpowered.  As an aside More than once in the ICW when motoring at 5-6 knots even when I turned into the four foot wake of a big sports fisherman going 20+ knots I have had a wave break over my bows.  I have seen multiple posts about reefing a C27/C28 at twenty knots.

Maybe I am wrong about all of this but it sounds to me like you hit a one time wave and were not really overpowered.

Do you now or have you ever owned and raced an F27/28/31?

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Peter.... being relative new  do you sail ( measure ) the true wind or apparent ?  15 true and going 15 might be just a tad more wind than you think. My 28 R when pressed hard with good crew was diving at times. But every sheet was in hand and everybody was ready to dump ( not just release ). in flat water and perfect conditions we had it up to 24 knots at one time.  18 ish a lot .

My Farrier F 33 is behaving much more docile and I had a beginner sailor on the helm when we went 23 knots ( I was very close to grab stuff from him ) and again sheets in hand. Never had the float submerged on the F 33....  but also I reef early and be much more cautious than most. 16 on the big boat feels like 10 on the 28 R..

 

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3 hours ago, Wess said:

Do you now or have you ever owned and raced an F27/28/31?

Nope, but I have hit waves when sailing on them.

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The limit is when you lose steering because the rudder is out of the water. You still have a way to go so yay. 

Steer down in the gusts and if you bury the nose hard you should have a moment to ease the main. This is good to practice on flat water.

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I wouldn't recommend the above when going to weather...

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Lots of posts from people who have never sailed an F-27/28. I own and actively race my F-27

You have a 28R so you have a longer rotating mast, and more sail area so you need to be more careful. We have the same floats, but your boat is likely a little lighter due to no aft cabin, smaller main cabin, this will mean your float will submerge later than mine.  My rule is that when you see continuous green water over the leeward float its time to do something different, but not a freak out moment. If its just occasional from waves then just keep pushing.  You will feel/see water slamming into the beams and slowing the boat. If boat speed is above about 14kts the mainsheet is in my hand and usually autopilot is off. With crew the screacher/spinnaker would always have a hand on it, without crew/not racing I would probably reduce sail in that situation at night.

 

 

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9 hours ago, Mizzmo said:

Lots of posts from people who have never sailed an F-27/28. I own and actively race my F-27

 

 

I wrote my response from the cabin of my f27. Does that mean I'm one of the cool kids?

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On 8/9/2020 at 7:59 AM, Mizzmo said:

Lots of posts from people who have never sailed an F-27/28. I own and actively race my F-27

You have a 28R so you have a longer rotating mast, and more sail area so you need to be more careful. We have the same floats, but your boat is likely a little lighter due to no aft cabin, smaller main cabin, this will mean your float will submerge later than mine.  My rule is that when you see continuous green water over the leeward float its time to do something different, but not a freak out moment. If its just occasional from waves then just keep pushing.  You will feel/see water slamming into the beams and slowing the boat. If boat speed is above about 14kts the mainsheet is in my hand and usually autopilot is off. With crew the screacher/spinnaker would always have a hand on it, without crew/not racing I would probably reduce sail in that situation at night.

 

 

 

On 8/9/2020 at 8:00 AM, Mizzmo said:

one more thing. Join the F-boat forum, you will get a lot more informed responses to your questions https://fct.groups.io/g/main

 

What he (^) said.

Minor additions or perspective...  we had no autopilot or cleated sheets rule at 10-12 knots of boat speed (and things were handed to crew w knowledge and experience to know how to react at that stage... no newbies).  And while its highly unlikely to go over in 15 knots of breeze in any sail configuration or sea-state and I agree a buried float (on an F27) on a reach or upwind course is not an issue - we have actually had the main hull flying and daggerboard showing on occasion while close reaching under screacher (this ain't fast BTW) - if this was happening at all on a downwind course I would be extremely concerned.  But its also unlikely to happen in the conditions described unless the sea state is extreme.  I don't mean it can't happen.  We have stuffed and lifted the ass and rudder out going down wind in similar w wind against current sea state.  Skilled hands on sheets are what is needed at that stage (to give a big ease).   As Mizzmo said an F28R is easiewr to put over than an F27.  Whomever told you its tame compared to an F27 or F31 steered you wrong.  Treat an F28R with respect.

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2 hours ago, Wess said:

 

 

SNIP

As Mizzmo said an F28R is easiewr to put over than an F27.  Whomever told you its tame compared to an F27 or F31 steered you wrong.  Treat an F28R with respect.

Not disagreeing with any of this.

My question is about the pecking order of fboats in being tame.  Truth be told I am looking for ones that are very tame.  Currently suppose to look at a Dash and C27 in the Florida Panhandle (as soon as the weather clears up a little).  I was under the impression that the newer flavors with bigger amas were safer and less prone to pitch pole; but this is only from reading.  I have only sailed on fboats in nice weather except for one ride on a F39 that was screaming and had a very experienced skipper.  My first choice is still to get a C36 in Europe and cruise the canals and easy coastal sailing in the summer but that low down dirty COVID-19 put an end to that.

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2 hours ago, Tomfl said:

Not disagreeing with any of this.

My question is about the pecking order of fboats in being tame.  Truth be told I am looking for ones that are very tame.  Currently suppose to look at a Dash and C27 in the Florida Panhandle (as soon as the weather clears up a little).  I was under the impression that the newer flavors with bigger amas were safer and less prone to pitch pole; but this is only from reading.  I have only sailed on fboats in nice weather except for one ride on a F39 that was screaming and had a very experienced skipper.  My first choice is still to get a C36 in Europe and cruise the canals and easy coastal sailing in the summer but that low down dirty COVID-19 put an end to that.

If you are looking for tame Fboats, look at the F24 mk 2.  No need to reef in winds up to 35 kts--I reefed mine (12 years and 6000 miles sailing it) 3 times and I raced it hard (and single handed) in San Francisco Bay and the Carquinez Straits.  The 3 reefs occurred in races offshore to the Farallone Islands with the winds in the mid 30s and 14 foot rollers (I was more afraid of the waves than the wind). 

You can also intentionally depower any fboat sailplan with new sails that you tell the sailmaker to make with less camber.  

And "please" stop calling an F27 a C27.  Give Farrier his due.  

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IMHO in terms of cruising safety,  it goes:

F-44

F-36/F-39

F-27/F-28

F-24/F25A (Only based on the shorter waterline/probably marginal difference between the F-27)

F-22

F31/F-9/F-33

Dash 750

F28R

F31R

Sprint 750

F31OD

F-25C/85

FWIW I have only sailed on an F-31 R and F-27. I have raced against most of these though.

 

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Hey Mizzmo, why rank the f44 cat safer than the F39 tri?  Just curious. 

-Greg (about to sail my F36/39 1,500 miles upwind in Pacific hurricane season :)

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Headed to San Francisco?

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On 8/13/2020 at 6:05 AM, Mizzmo said:

IMHO in terms of cruising safety,  it goes:

F-44

F-36/F-39

F-27/F-28

F-24/F25A (Only based on the shorter waterline/probably marginal difference between the F-27)

F-22

F31/F-9/F-33

Dash 750

F28R

F31R

Sprint 750

F31OD

F-25C/85

FWIW I have only sailed on an F-31 R and F-27. I have raced against most of these though.

 

 Just curious - how would you situate the F32SRCX (e.g. Jailbreak/Taniwha/Carbon Credit) on this list? Or are those essentially one-off builds?

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 2 seasons on my F24mk1 and it is rock solid stable.  Had it in rougher seas (1-2 meters rolling, bow jumping out of the water and slaming every few waves) and was in full control.  But I am a family sailor and need to keep the family happy so often times we are more looking for ways to slow the boat down.

Here we are in 15-20kts and I got the boat trimmed down to 5kts because the kids wanted to play on the nets.

20907A87-06AB-45D6-9802-9BAAE657BD35.jpeg.f11665fe781b74693c05a40e88626637.jpeg

caveat, I don’t have performance sails and I am pretty sure my boat weighs a ton but I almost never reef and the few times I did burry a float the boat didn’t even flinch.  

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Your kids will remember playing on the nets their whole lives.  My 30 somethings still mention how much they loved boat trips.  You're a good dad.  We look forward to chartering all together (with spouses now), in a warm place when covid settles down.

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On 8/13/2020 at 3:05 PM, Mizzmo said:

IMHO in terms of cruising safety,  it goes:

F-44

F-36/F-39

F-27/F-28

F-24/F25A (Only based on the shorter waterline/probably marginal difference between the F-27)

F-22

F31/F-9/F-33

Dash 750

F28R

F31R

Sprint 750

F31OD

F-25C/85

FWIW I have only sailed on an F-31 R and F-27. I have raced against most of these though.

 

Why the major difference between the F25A and the C? Or the 31 and the 31R. One reef and you have compatible SA./D. The F85SR is compatible with the F82R, with improved floats. Basically LWL helps when you need to battle wind and waves

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On 8/14/2020 at 1:15 AM, Ravenswing said:

Hey Mizzmo, why rank the f44 cat safer than the F39 tri?  Just curious. 

-Greg (about to sail my F36/39 1,500 miles upwind in Pacific hurricane season :)

I based it primarily on hearsay and waterline length. I believe Ian said that the primary driver for safety on these boats was sail area to displacement and volume forward. I think the F41/44 have lower SA/D ratio than the F-36/39..

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On 8/16/2020 at 9:08 AM, nyker said:

Why the major difference between the F25A and the C? Or the 31 and the 31R. One reef and you have compatible SA./D. The F85SR is compatible with the F82R, with improved floats. Basically LWL helps when you need to battle wind and waves

The designer of these boats specifically cautioned sailors based on their power. Sure an F31R double reefed is safer than an F-31with full sail, but most of the time people get into trouble with the boats its related to rising wind and not reefing early enough.

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For a lot of the capsizes that have occurred, it is not the static forces which have their root cause but dynamic issues.   Waves 1/2 the boat length or so, for example, and wave shape may reduce rudder effectiveness and cause one to lose control.  Also,  simply lulling the helmsman into sense of security as you gradually have winds speed up with spin.  First the mainsheet is let out to keep the boat on its feet, but eventually that isn't effective (main already out all the way) then you have a bigger likelihood of a gust driving you down and out.

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1 hour ago, Mizzmo said:

I based it primarily on hearsay and waterline length. I believe Ian said that the primary driver for safety on these boats was sail area to displacement and volume forward. I think the F41/44 have lower SA/D ratio than the F-36/39..

I am not sure it’s that simple for many sailors of these boats. My God just read some of the comments on here. The benefit of the lower buoyancy floats is that they talk to you much earlier for the same power to weight ratio. Helps those less experienced avoid getting themselves in over their heads and that adds to “safety.”

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If burying the lee ama is no big deal then you don’t have the critical information where it actually matters. Once the lee ama is submerged you’re in the negative stability zone (not as steeply negative as flying the main hull, but negative) — more heeling momentum brings less righting momentum. I think the right cruising tri design needs the amas sized so that burying one is the “oh shit” moment, not the “let’s see if I can ride this one out” moment.

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On 7/29/2020 at 8:53 AM, gspot said:

The Farrier 2012 Sailing Manual is a great resource. Check out page 20 for some thoughts on this topic:

It is not unusual to drive the low resistance float bows through waves, or even submerge the float in some circumstances. This has been found to have no adverse effect on the boat, and in fact the boat will tend to round up slightly, not slew to leeward as commonly and mistakenly believed.

Early Farrier designs used low buoyancy floats, and frequently completely submerged the leeward float, with speeds in excess of 15 knots, for quite some time, with no ill effect on the boat. However, this is sailing on the limit, and don't push your luck unless prepared for a ducking.

Sea state is a significant variable in how hard you can push the boat - it's much safer to push hard in flatter water (e.g. offshore breeze).

Page 52 of the aforementioned Farrier 2012 Sailing Manual also includes some capsize limits based on wind speed for some models so you don't have to rely on the lee ama submerging to know things are getting tenuous:

image.png.4511d04d1c936d147f4d051826f10de2.png

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20 minutes ago, gspot said:

Page 52 of the aforementioned Farrier 2012 Sailing Manual also includes some capsize limits based on wind speed for some models so you don't have to rely on the lee ama submerging to know things are getting tenuous:

image.png.4511d04d1c936d147f4d051826f10de2.png

Sure, if you know what the true wind speed is...which doesn't happen often in the smaller boats and in some places the ave-gust-lull percent can be 100% or more.  If you want to be safe, sail in your bathtub with a fan.  Sailing a tri is supposed to be an adventure, right?  

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1 minute ago, MultiThom said:

Sure, if you know what the true wind speed is...which doesn't happen often and in some places the ave-gust-lull percent can be 100% or more.  If you want to be safe, sail in your bathtub with a fan.  Sailing a tri is supposed to be an adventure, right?  

It's not 100% reliable but stationary flags can provide some good insight into wind strength.

I use the basic rule of thumb that if a stationary flag is flying straight out from the flagpole then the wind is about 20 knots, and if the "leech" of the flag is lifting upwards the wind is 25 knots or more. This just happens to correspond nicely with the recommended wind speeds for reefing our F-82R.

If you live in an area with lots of squalls or thunderstorms all bets are off and you need to simply need to watch out if you see that stuff coming! 

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On 8/13/2020 at 6:58 AM, Tomfl said:

Not disagreeing with any of this.

My question is about the pecking order of fboats in being tame.  Truth be told I am looking for ones that are very tame.  Currently suppose to look at a Dash and C27 in the Florida Panhandle (as soon as the weather clears up a little).  I was under the impression that the newer flavors with bigger amas were safer and less prone to pitch pole; but this is only from reading.  I have only sailed on fboats in nice weather except for one ride on a F39 that was screaming and had a very experienced skipper.  My first choice is still to get a C36 in Europe and cruise the canals and easy coastal sailing in the summer but that low down dirty COVID-19 put an end to that.

bigger amas mean more righting moment so more speed and more lift. the less load on the main hull the higher it comes out of the water the better the chance of a pitch pole.

IMHO if you can fly the mainhull you can pitchpole the boat as when the ama bites in the boat starts to rotate before the main hull gains any buoyancy to prevent that.

WIth bigger ama it might help going over sideways with a screacher up and not eased in a huge puff....

 

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On 8/13/2020 at 10:15 PM, Ravenswing said:

Hey Mizzmo, why rank the f44 cat safer than the F39 tri?  Just curious. 

-Greg (about to sail my F36/39 1,500 miles upwind in Pacific hurricane season

Trimaran owners do stupider things?

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3 hours ago, MultiThom said:

Sure, if you know what the true wind speed is...which doesn't happen often in the smaller boats and in some places the ave-gust-lull percent can be 100% or more.  If you want to be safe, sail in your bathtub with a fan.  Sailing a tri is supposed to be an adventure, right?  

Dude, this is data that someone (Ian) thought long and hard about. Take it for what it is.

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11 hours ago, Russell Brown said:

Dude, this is data that someone (Ian) thought long and hard about. Take it for what it is.

Yah, Ian was pretty good with static forces (that's what designers did in his era (a lot of them even today)) but he never considered the safe operating envelope of other environmental factors such as wave height and shape and how gravity (down the slope of a steep wave) changes the ability of a boat to stay upright.  Something drummed into a submarine dive officer (me, for example) your safe operating envelope depends on depth, angle, speed if you want to return to the surface.  I do take it for what it is, a SWAG.   

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4 hours ago, MultiThom said:

Yah, Ian was pretty good with static forces (that's what designers did in his era (a lot of them even today)) but he never considered the safe operating envelope of other environmental factors such as wave height and shape and how gravity (down the slope of a steep wave) changes the ability of a boat to stay upright.  Something drummed into a submarine dive officer (me, for example) your safe operating envelope depends on depth, angle, speed if you want to return to the surface.  I do take it for what it is, a SWAG.   

The 2012 Farrier Sailing Manual does also say:

The wind capsize figures given in table below are the theoretical wind speeds required to lift the center hull in the worst possible condition, which is side on with sails sheeted in tight - something that should never be allowed to happen. These figures are based on calculation combined with many years of sailing trials and testing in all conditions.
 
While every care has been taken, this table should only be regarded as a general guide, and it always remains the skipper's responsibility to ensure the boat is sailed safely and sail is reduced appropriately for the conditions.

The recommended safe wind speed range should be thus modified or varied when required as follows:

If winds are inconsistent, strong and gusty, reduce the recommended safe wind speed ranges by 20%.

If offshore, or in isolated areas, then reduce the recommended safe wind speed ranges by 20%.

If crew is inexperienced then reduce the recommended safe wind speed ranges by 20%.

If running directly downwind, the above safe wind speed ranges still apply. However, mainsail should be reefed early, or dropped altogether should winds exceed 30 knots and use a headsail only instead. Headsails can be easily released in strong gusts from astern. A mainsail cannot.

If boat is lightly loaded, the wind capsize figures will be lower, and extra care may be required. However a light boat also accelerates more easily, which helps absorb gusts easier.

Main plus Screacher capsize wind speeds ranges are around 10% lower than the main plus jib figures. However, the lighter cloth usually used on these light weather headsails will restrict their use to low wind speed ranges

So yes a guide, but he does take into account other environmental factors, and still slightly better than a SWAG IHMO.

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Hey, he did the best he knew how.  I'm not saying his chart/disclaimers are totally without merit.  But think about what he did write..."wind side on with sails sheeted in tight which should never happen".  Totally ignoring boat speed and boat angle which are significant factors in most of the pitchpoles I know about.  Think about what you have experienced when you bury the lee ama and catch the aka.  The boat lurches to a halt and the stern rises causing the vaka bow to bury sometimes.  Like a pole vaulter, the speed/momentum transforms into angular acceleration. The amount of bury depends on boat speed (and  the  stern rise may continue if sails are not released since that is the situation where the wind would then be side on with sails sheeted tight).  Now think about what happens if you are going down a slope and the same thing happens....the stern is already lifted so you are that much closer to moving the center of mass past vertical which may cause you to flop over onto the other side.  It is possible to create a true safe operating envelope for your boat, but it would have more do with boatspeed, weight and angle more than wind speed.  

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I totally agree with your comment on boat speed, which is also mentioned in the 2012 Farrier Sailing Manual:

In general, the risk factor will only begin to increase when boat speed exceeds 15 knots while reaching, or about 8 knots to windward.

The OP was asking for advice on limits for his boat, and while not perfect I think Ian did provide some reasonable guidance.

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On 8/18/2020 at 2:06 PM, MultiThom said:

It is possible to create a true safe operating envelope for your boat, but it would have more do with boatspeed, weight and angle more than wind speed.  

After writing this, I decided to actually calculate it.  Turns out weight doesn't matter.  Basically you are converting kinetic energy to height, so the calcs boil down to the safe speed is the square root of (product of 9.8 (gravity) times your boat length in meters).  Convert that number to knots if you aren't familiar with m/s.    That's for flat water.  For my 6 meter boat, no pitchpoles possible unless going 15 knots plus in flat water.  Once wave height gets to be half boat length (3 meters in my case), I have to reduce speed to 10 kts to be safe from pitchpole (depending on wave period (steepness)).   

The OPs query for an F28 (8.5 meters) gives you safe flat water speed of 17.8 kts; In waves of 14 feet or more, OP should reduce speed to 11 kts to be safe from pitchpole.  

Ian's "blow me over" calcs still apply for wind driven capsizes (not pitchpoles).

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22 minutes ago, MultiThom said:

After writing this, I decided to actually calculate it.  Turns out weight doesn't matter.  Basically you are converting kinetic energy to height, so the calcs boil down to the safe speed is the square root of (product of 9.8 (gravity) times your boat length in meters).  Convert that number to knots if you aren't familiar with m/s.    That's for flat water.  For my 6 meter boat, no pitchpoles possible unless going 15 knots plus in flat water.  Once wave height gets to be half boat length (3 meters in my case), I have to reduce speed to 10 kts to be safe from pitchpole (depending on wave period (steepness)).   

The OPs query for an F28 (8.5 meters) gives you safe flat water speed of 17.8 kts; In waves of 14 feet or more, OP should reduce speed to 11 kts to be safe from pitchpole.  

Ian's "blow me over" calcs still apply for wind driven capsizes (not pitchpoles).

Just curious - Is this just for kinetic energy alone or does this also include the effects of windage on the sails and/or the rig when the boat stops dead from burying the bows?

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40 minutes ago, gspot said:

Just curious - Is this just for kinetic energy alone or does this also include the effects of windage on the sails and/or the rig when the boat stops dead from burying the bows?

That's just the KE, that's why you still have to release sheets if you bury the bows since the sails can still push you the rest of the way over if sheeted.  

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13 minutes ago, MultiThom said:

That's just the KE, that's why you still have to release sheets if you bury the bows since the sails can still push you the rest of the way over if sheeted.  

dumping the main is usually the cause of going over the front depending where the wind ends up as your huge flag at the top of the mast just pushes you in

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49 minutes ago, Sailabout said:

dumping the main is usually the cause of going over the front depending where the wind ends up as your huge flag at the top of the mast just pushes you in

In big waves I think that is very true. But if you want to learn the limits of your boat, you do that in flat water.

In my F27, I stuffed the bows once while looking for the limit (main screecher, flat water). Screecher sheet was being held in hand so it was easy choice. 

Once by surprise after having just dropped the spin and rounded a bottom mark and reaching over to a separation mark. Gust hit, buried bow came to what felt like a complete stop (it wasn't) I released the main because my crew had been tossed forward on the tramp to front beam and that was the only action available to my small brain. And the boat popped right up, the rudder got some grip and we rounded up a little. YMMV

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On 8/14/2020 at 6:04 AM, Training Wheels said:

Headed to San Francisco?

Yep, going nuts back here at home with my tri sitting alone in MX. Long range cruising southbound isn't realistic for us in Covid-time so we want to get Ravenswing back to SF and enjoy her locally.  It's a bit nerve wracking watching the hurricanes march this season...

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10 hours ago, Ravenswing said:

Yep, going nuts back here at home with my tri sitting alone in MX. Long range cruising southbound isn't realistic for us in Covid-time so we want to get Ravenswing back to SF and enjoy her locally.  It's a bit nerve wracking watching the hurricanes march this season...

Bummer, we’re in Banderas Bay. I was hoping to run into you down here and check out your boat!

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14 hours ago, Ravenswing said:

Yep, going nuts back here at home with my tri sitting alone in MX. Long range cruising southbound isn't realistic for us in Covid-time so we want to get Ravenswing back to SF and enjoy her locally.  It's a bit nerve wracking watching the hurricanes march this season...

Best wishes. Sail safe. 

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thanks for the wishes Wess!  

Training Wheels, we'll be back.  Jeanne and i loved having the boat in LaCruz and i want to spend a whole season checking out the area. I had eleven people aboard Ravenswing one fine early March day, with whales watching up close. Cracked off the wind a bit to head towards the barn and in that lovely warm Banderas breeze we were jamming at 15 kts for a bit. Didn't know we could do that with an extra ton of humans aboard!

If you haven't walking-toured the new wall murals in the LaCruz village, please do. Beautiful work by all-local artists. The municipality held a contest and picked 25 artisans out of hundreds of applicants. Our traveling party got to attend the 'unveiling' walk - that was lots of fun, even though COVID crazy was just days away...

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Excellent, hope to share an anchorage with you!

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On 8/20/2020 at 9:28 AM, rustylaru said:

In big waves I think that is very true. But if you want to learn the limits of your boat, you do that in flat water.

In my F27, I stuffed the bows once while looking for the limit (main screecher, flat water). Screecher sheet was being held in hand so it was easy choice. 

Once by surprise after having just dropped the spin and rounded a bottom mark and reaching over to a separation mark. Gust hit, buried bow came to what felt like a complete stop (it wasn't) I released the main because my crew had been tossed forward on the tramp to front beam and that was the only action available to my small brain. And the boat popped right up, the rudder got some grip and we rounded up a little. YMMV

yes if the main hull can gain some buoyancy then your ok

Beach cat is where you learn about going over...

reaching always an issue as your escape might be going up or down..

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