Sailing with Just Your Genny

[CharlieJ]

The area is magnificently well marked with bouys and clear chanels etc. And at that time of day you could just see the mud and sand banks in that area. Oh well.

No you can't see that- not if your head is up your butt you can't  :o

His obviously was well planted ;D

[AdriftAtSea]

I stopped doing it after having read that and my rig is still up.

Ah, but you cannot prove a hypothesis by showing a negative.  You cannot say that your rig would have failed had you kept doing that. 

Sorry, it's a nitpick.  ;)

Sailing with headsail alone is a long established heavy air tactic; as is using twin headsails off the wind for 'trade wind' sailing.  There are countless instances of boats being sailed in this fashion without rig failures, so I think to assert causalilty is a bit of a reach.

Just what force is on the rig with headsail only that is not present with both main and headsail?  The weight of the mainsail itself?  I'd argue this is neglible compared to the forces produced by the sails from the wind.  The direction of the force produced by both sails from the wind is roughly the same (eg, both sails are pushing forward while close hauled).  Therefore, if the rig can handle main+genny, it can certainly handle genny alone.

I'd like to see a proper engineering analysis of those dismastings; I'd wager there's more to them than just sailing with genny alone.

While CaptainSmollet has covered the disadvantages of sailing under a genny alone pretty well, i think his analysis of the mast failure due to sailing under a genny alone is a bit off. 

If your boat has a bad backstay, then sailing with just the genny up can put the rig at risk.  The mainsail does exert a rearward force on the mast, at least to some degree, especially when sailing close hauled. 

If you think about it... the mainsail is held to the boom and the downward force on the boom, as provided by the boomvang and the mainsheet, as well as the weight of the mainsail and boom, will be transmitted to the mast via the cloth in the mainsail.  While this force isn't extremely high, it can often be enough to save the rig, if the backstay breaks.  On a boat with a bad or weakened backstay, then sailing without the mainsail up, may be the difference between having the backstay snap and losing the rig or not.

The mast is not isolated from the mainsail and the tension that the mainsail is under.

[Captain Smollett]

If your boat has a bad backstay, then sailing with just the genny up can put the rig at risk.  The mainsail does exert a rearward force on the mast, at least to some degree, especially when sailing close hauled. 

If you think about it... the mainsail is held to the boom and the downward force on the boom, as provided by the boomvang and the mainsheet, as well as the weight of the mainsail and boom, will be transmitted to the mast via the cloth in the mainsail.  While this force isn't extremely high, it can often be enough to save the rig, if the backstay breaks.  On a boat with a bad or weakened backstay, then sailing without the mainsail up, may be the difference between having the backstay snap and losing the rig or not.

The mast is not isolated from the mainsail and the tension that the mainsail is under.

I am still waiting to see a real engineering analysis of a rig failure CAUSED BY sailing with headsail alone.  Many, many cruising boats sail the trade winds with twinned headsails and no main, and I don't think the rate of incidence of rig failures has been shown to be higher in these cases.

In other words, we can speculate all we want to, but I want to see some real data.  Has there been a real correlation (forget cause and effect, at this point I will settle for simply seeing a correlation) shown between sailing headsail only and rig failure?

I don't think there has, or we would have ALL read about it in the countless books and magazine articles we read.  But rather, the converse IS true - headsail only sailing is advocated as a downwind technique and even a heavy weather technique where warranted by balance.


By your arguement, sailing with main alone would stress the rig more than with both sails, but the stressed area would be the forestay and fittings.  After all, the jib/genny IS providing support in the form of luff tension to the rig.  So, should we all fly all sails all the time?

I'm sorry if my last comment sounded sarcastic, but I'm having a hard time imagining how say (to take my small boat) 150 sq ft of sail area providing lift (or drag) can stress the rig CONSIDERABLY less than the roughly 60 sq ft of jib only.  Here,  "considerably less" implies that rig failure is LIKELY with headsail alone and MUCH LESS likely than rig failure with mail+jib. 

Heeling moment does not lie - it, along with boat velocity, shows the net force on the rig.  Sorry, but we are dealing with very basic stuff here in the form of Newton's Second and Third Laws.  Drop a sail, either one it does not matter, and the combined net force vector of heeling moment and boat velocity decreases.  In other words, less force on the rig.   Period.

The whole thing seems a bit like a cop-out to me: rig fitting fails, someone takes the easy way out and says it is because the sailor sailed with headsail alone.

[AdriftAtSea]

Captain Smollett-

Please note, I did clearly state that the backstay had to be compromised.  If fact, a friend of mine used their main to help hold the mast upright, when their backstay failed, and also so turned upwind to help use wind pressure to hold the mast up.  Then they took their topping lift and attached it to the backstay chainplate, to use as a temporary backstay.

[Captain Smollett]

Right, AFTER the backstay has failed, the main can help support the rig.  No arguements there.  The issue I have is the assertion made earlier in the thread that sailing with headsail alone will CAUSE rig failure.

I've pretty much said what I need to say on this topic.  It was fun to theorize and speculate, but now, until we see some actual data, I have nothing else to contribute.

[s/v Faith]

Sailing with just your head sail, beats the heck out of talking about sailing on the internet.....  ;D

Laziness.. ;D

  That is my reason....

There are days when I only have a little bit to sail.  I often go out anyways.

  Sometimes when I carry not just my own cares out on the water, but those of others I just need to get underway

  I can sail out of my slip, and be under way with just the genny, in a minute or so.  Usually I can get out on the water with very little sound, or strain. 

  The drive is less then optimal, but sometimes you just don't care about making hull speed (although, sometimes it comes close).

  The man I bought the boat from had some health issues, and he used to go out like this some times.  It was the only way he could sail.  Maybe that is why 'Faith' understands, and just sails so well like this.   :)



 

[Captain Smollett]

Sailing with just your head sail, beats the heck out of talking about sailing on the internet.....  ;D

Boy, you got THAT right, and you can say that again.  Here, I'll say it again for you.

Sailing with just your head sail, beats the heck out of talking about sailing on the internet.....

;D ;D

[AdriftAtSea]

Sailing with just your head sail, beats the heck out of talking about sailing on the internet.....  ;D

S/V Faith shoots, and scores...nothing but net... :D Going out Thursday for a long weekend.

[Norm]

OK guys...  many years ago I read in a prestigous yachting magazine about the jib contributing to mast failures.  The context was that yawl and ketch rigs must not be sailed under jib and mizzen only.  This wil bring down the mainmast, the article claimed.  Harumph, dad had us sailing under jib and mizzen for years aboard our old Alden yawl. 

Thinking I'd caught him out, I asked dear old dad, a civil engineer and PhD in Physics for an explainantion.  He read the magazine article, thought for a bit, and declared it bunk.  Then, in dad's inimmicable way, he had me nip off for a pencil, paper, slide rule, book of log tables, etc. and he proceeded to prove it to me using science.  I have long since forgotten the proof.  Though dad is still with us and as articulate as ever... I would never presume to admit that I had forgotten the proof and needed a review.  I accept the premis as bunk.

I challenged him once more during my teen years and lost again.  Amazing.

[AdriftAtSea]

But Norm, as a teenager, you should have known everything in the world... or at least that is what most teenagers think at the time... fortunately, they usually survive to grow out of that. 

A properly rigged boat is really under no danger, IMHO, from sailing just under the genny.  However, there probably will be some sail plan balance issues, that would not arise from sailing under a main and genny.  Lee helm will probably be an issue, as might having some difficulty tacking. 

[Captain Smollett]

I think I've read some of this before.   ;)

[Norm]

A "Lab Report" from last weekend:

Friday and Saturday Elizabeth and I took off for some quiet time sailing one of the club's Beneteau First 35s5 sloops.  We sailed out of Boston Harbor with no destination in mind.  The light air led us into Scituate Harbor Friday night.  Saturday, we returned to our berth in Boston. 

Saturday, the wind got into the 20s with some gusts reported in the low 30s.  We sailed under 120 % genoa all day and on all points of sail.  We were feeling kind of lazy and felt that a test of the SailFar discussion might be interesting.

Our brief observations are:
Running is not very efficient but gybing is easy.  The boat rolled a lot being underpowered.  The genoa is not too stable so it fills and collapses often, rolling the boat.  An outboard lead or a pole may have helped.  We rigged nothing as the leg was a short one out the harbor to the sea buoy.

Broad Reaching was flat and fast.  We rigged an outboard lead.  Elizabeth got into the groove steering smartly in the quartering seas.  The boat scooted along at 6 plus knots and showed us an "eight" for a brief moment.

Close Reaching, Beating, and Tacking worked out fine.  The boat sailed slower than does with a reef in the main in these conditions.  Close hauled required steering care or the boat would stall.  Inspite of the headsail-only configuration, the Beneteau rounded up in gusts.  We'd have preferred no headsail and a reefed main while going closer to the wind.

We watched the mast as we sailed in the chop and swells.  The rig is a double swept back spreader arrangement with a 7/8ths fractional headstay and no runners.  (Geek-babble)  At no time did we sense any unusual loading or pumping of the rig.  The conditions were puffy 20-30 kts with 2-3 foot swells and chop.

Observations of other boats sailing under headsails only interested us, too.  Both Elizabeth and I commented that deeply rolled up genoas seemed to be very mishappen, round and pulled hard at the middle of the headstay.  We wondered if  such loading... middle of the head stay vs the extreme ends... lead to any rigging failures.  We seriously doubt a little sail could do so.

So... we continue to beat this old horse...
Best regards, Norman

Note:  We could not find a place for breakfast ashore in Scituate Harbor!  I don't know that I have never been able to find a waterfront breakfast place in a busy harbor before this trip.  Remarkable.

[Pixie Dust]

Interesting observations Norm.  I too have a 120% Genoa and was trying out just the head sail one day.  Lots of wind and current, but when I got to the pass, I could not tack.  The windage on my boat and the current against me would not let me bring her around enough to tack.  I actually was surprised.  Once I put up the reefed main, I had total control of the situation again.   
Thanks for sharing the observations!!

[Norm]

Interesting story.  With the wind and current conspiring against you, tacking is a very real problem.  This is compounded by the short keels common on small cruising sailboats.

It is good to test configurations in various conditions.  I still like mainsails to be "up." The main sail really does help.  Could be why it is called the "main" sail?  Haha.

Elizabeth and I purposely sailed the boat in a configuration we would never normally choose.  We did so as a test.  We both prefer the main with a reef to a headsail only.  It is sometimes more work.  It always provides control.  Sailing in and out of harbor requires control. 

Note.  in '94, I sailed a 67 ft racing machine across the Pacific.  We took the main down only once because of high winds.  We reached along comfortably under a small jib and staysail.  The problem was the mainsail fabric was compromised.  The main was lowered to protect/preserve the sail.  There isn't much maneuvering during a 5,000 mile leg. 

[AdriftAtSea]

And the main on a 67' boat is probably a pretty penny... :D

Was out day sailing three days earlier this week, as I spent the week down at the boat. 

On Monday, I was feeling lazy and tried sailing on just the 150% genoa and got pretty similar results to what Norm reported, and my boat is rigged like the Beneteau he was on—double swept spreader, 7/8s fractional rig.  Tacking was a bit more tricky, probably due to the fact that I'm on a trimaran, not a monohull and I had to be careful not to backwind the genny accidentally.  Part of the problem was the amount of wind...was five knots or less most of the day.  UGH...

[CapnK]

P.S about three hours later we heard on Channel 16 that a boat that we are 99% was them had continued on and run aground on a sandbank (that was directly in front of the course they had been sailing on when we encountered them) and they were looking for a rescue tow.

And that, *that* is known as "sweet Justice". ;)

I used to sail my Com-Pac 23D under headsail-alone frequently - in fact, the first time I ever sailed it offshore was that way, on a blustery summer day with a good-sized swell running. For the first couple of years the boat had the original aluminum flat-plate rudder, and consequently lots of weather helm in stronger winds. Sail-setting/dousing strategy was thus: main and fore in lighter wind, as the wind picked up, I reefed the main, then dropped it, then switched from the 120 down to the working jib. Keeping the CE as far forward as possible was the only way to sail comfortably.

The boat just wouldn't do much better than a reach under main alone, with that plank of a rudder. After I fitted a foiled rudder to the boat, there was a world of difference in how she handled, and I sailed with both sails more often in higher winds. Never did it seem as if the rig was overloaded under foresail alone. Whenever I thought about "what if the backstay fails", I did my best to put it out of my mind (there was nothing I could do til it happened, so why worry ;)). The standing rigging was of an indeterminate age, but appeared to the eye to be in good shape, so I didn't worry too much. When conditions warranted, I simply did what I could to lessen any strain it was under.

As I rerigged the boat, however, that question came to mind, and so I ran a small extra halyard aft which, in the event of backstay failure, I hoped would allow me the time to do what needed doing to keep the rig up. I used a high-strength climbers line for this, which thankfully never had to serve that emergency function. It did, however, save my bacon on another occasion, a story for another time... :)

I guess my point is that except under extreme conditions, I think most rigs are engineered strongly enough that *if the rigging itself is in decent shape and tuned properly*, the rig is plenty strong enough to handle the stresses of foresail-only sailing. Tired wire or poor adjustment (or both) are the most likely causes of any rig failing. Avoid those, use good judgement when determining what size of sail to set, and it shouldn't be a problem which sails get set where.

Prudence and awareness naturally dictates that if the boat is leaping off of wave crests, it's time to shorten sail and lessen loads on the rigging, irregardless of what sails you have up. :)

Two things from many thousands of miles of Hobie Cat sailing that perhaps bear mentioning here:

Hobie 16's don't even have a backstay, the shrouds are just led slightly aft. This works fine for jib-only sailing, and when the main is up, it and the mainsheet function as the backstay.

And being able to tack a H16 in 25+ winds with 4-6' swells, I found that that knowledge translates well into tacking a monohull which is sailing under foresail-only. Prior to tacking, fall off a couple of degrees to get a little extra speed. Sheet in and keep the sail trimmed and powered up as you turn into the wind. Watch the waves, and try to time the tack so that you are coming through the eye of the wind *as you come off the back of a wave*. Not only does the 'downhill' help keep speed up, it also lessens the amount of boat-surface-area that the wind can act upon. Let the foresail backwind until you are through the eye, and then once on the new tack you can switch it over. You'll always wind up falling off a bit more than needed, but at least you won't blow the tack. :)

[Captain Smollett]

Hobie 16's don't even have a backstay, the shrouds are just led slightly aft. This works fine for jib-only sailing, and when the main is up, it and the mainsheet function as the backstay.

My little boat is rigged similarly.  It uses a "3 stay rig" where the shrouds double as twin backstays.

Did I read a while back that some of the larger McGregor's are rigged this way as well (I may have misread).  I was surprised the rig was used on a boat larger than 20 ft.

[s/v Faith]

Positive proof that sailing on just your Genny does not cause your boat to burst into flames and sink immedately.  ;D

[AdriftAtSea]

A small sailboat was tragically lost today, reportedly due to a fire and sank rapidly.  The captain, now missing and presumed lost at sea, would not leave the vessel, screaming something about the Genny didn't cause the fire according to several witnesses and VHF radio reports...  ;D

[s/v Faith]

A small sailboat was tragically lost today, reportedly due to a fire and sank rapidly.  The captain, now missing and presumed lost at sea, would not leave the vessel, screaming something about the Genny didn't cause the fire according to several witnesses and VHF radio reports...  ;D

;D :D ;D :D