Aftmast rigs???

Discussion in 'Sailboats' started by jdardozzi, May 28, 2002.

  1. gggGuest
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    gggGuest ...

    A mate was involved in the rig design on Mirabella V. I understand they were well on the way to finalising the boom design when he ran some calculations for the weight of water the boom might hold in a really big downpour with the water coming down the sail faster than it could drain out of the spar. The stress calculations had to be revisited!
     
  2. brian eiland
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    brian eiland Senior Member

    Dhow and Lateen Rigs

    How would you compare your rig with this modification made to another aft-mast vessel??
    http://www.boatdesign.net/forums/boat-design/wishbone-sailing-rig-1999-8.html#post283505

    ...also here
    http://www.boatdesign.net/forums/boat-design/wishbone-sailing-rig-1999-8.html#post283525

    You might consider looking thru these forums for other places to post your rig design (in addition to this one), that might bring you more responses in direct reply to your particular rig....such as dhow and lateen rigs.
     
  3. brian eiland
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    brian eiland Senior Member

    Atlantic 57 Cat Capsize recently

    I don't know what seas you sail in, but to say these conditions can not arise suddenly is just begging for interpetation. I've personally been off Hatteras sailing at night when the wind went from 10 knots to something over 30 in a matter of less the 1 minute....lets see triple the wind speed, square that figure for the wind pressure (6 times). On one other occassion it went from 10-15 knots to something over 60-70 in a matter of minutes.

    More recently there was a situation where an Atlantic 57 catamaran with two experienced owners onboard capsized in the Pacific due to a violent 60+ knot squall. Here is an interesting website reference and analysis:
    http://www.anything-sailing.com/showthread.php/6880-Capsize-of-Anna-a-Chris-White-Atlantic-57

    ....just a couple of excerpts:

    ...from the designer;
    "looked like the others more or less, though I was concerned that its movement seemed different. In any case, a few minutes after the initial wind gust and rain, the wind really cranked up and headed us. Then it increased again and headed us more. There was way too much wind for the sail we carried, so I luffed up enough to depower Javelin, trying to walk the fine line between flogging the sails violently and keeping our boat speed down below 12 kts. It was exciting, too exciting, and when it did not let up after a few minutes we dropped the mainsail entirely. If truth be told, the whole event left me pretty rattled. We experienced an increase from 20 to 45 kts of wind in a fraction of a minute along with a 90 degree wind shift. I did not expect that at all. And that's the lesson. Sometimes a squall will dish out something that you don't expect and are not prepared for. It may only be one out of 50 or 100 squalls that are truly dangerous but you don't know and can never be sure which ones they are."

    ...from the owners of the Atlantic 57;
    "I find that downwind in squally conditions a very deeply reefed main and a large light sail forward that can be completely eased off in an instant makes me more comfortable. Sails behind the mast are difficult to handle and impossible to depower quickly with the apparent wind aft of the beam."

    The point is that these BIG wind conditions can pop up, and very often a cruising sailor will just opt for turning off the wind and running with it. But then that mainsail is pinned against the mast and rigging, and it gets real difficult to drag it down into a reefed position...particularly a full-battened mainsail. All the while that mainsail is driving your bows down. Personnally if I am shorthanded I'd just as soon be without that tall full-battened mainsail in these situations.

    I've not done a similar calculation as Chris did on the overturning moment forces involved with this sail combo they were flying in those conditions, but I venture to guess my rig could have been carrying more sail area and not capsized in those same conditions.

    Here is a series of analysis on Chris' web pages:
    http://www.chriswhitedesigns.com/news/anna_capsize/index.shtml
     
  4. RHough
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    RHough Retro Dude

    Sailing for many is a hobby, like golf.
    Golfers practice, they spend hours and $$ on lessons and to practice the shots they find most difficult.
    Sailors? Just suggesting that a sailor might enjoy their hobby more if they got some lessons will start an argument.

    If sailors would spend 30 minutes a day, hell an hour a week learning something about weather patterns they could better identify the conditions and seasons that produce winds that they find hard to handle. The "did not expect" aspect is reduced or eliminated. Then they could go out in progressively poorer conditions and practice responses. The "was not prepared" aspect is reduced or eliminated.

    Why is it that a golf pro is always busy giving lessons at the local club so people can enjoy that hobby and very few yacht clubs have a full time pro to help people enjoy sailing?
     
  5. BATAAN
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    BATAAN Senior Member

    Here's another approach (not aft main) to battens that has worked for a long long long time.
    This 1000 sq ft main has T6063 aluminum pipe battens against the mast, sets very well, and does as it's told 99% of the time. This is the vessel's second mainsail as the first was worn out after 20 years of use. The price of docility and durability is weight, requiring a vessel with great stability.
     

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  6. pool
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    pool Junior Member

    A-frame rig alternative?

    Would an A-frame mast with a furling jib fwd and a furling boomless main aft be an alternative to an aft mast rig?

    Seems to have the pros of an aft mast setup, but easier to rig and sail being placed midships. It might also be easier on the eye to the traditionalist.

    Apparently, it was put successfully on a prototype cat in South Africa, and now starting a production run as a "SMG50" http://www.sail-the-difference.com.

    Tried to find out more, but could not find much about A-masts on the web, except a brief note on the mast designer's page here http://www.yacht-mast.de.
     

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  7. Fanie
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    Fanie Fanie

    That made some interesting reading (the capsize), such a shame it happened.

    RHough I agree with you. People are too lazy or ignorant to prepare themselves and do not think things through. I always try to reflect back on any and all experiences and try to either learn from it or seek an improvement that would cure such a problem.

    One of my own fears is exactly a squall you don't notice that can cause a problem - hence I was thinking again along the lines of a clutched cleat that can release a sail coming under excessive power. I cannot see it not working. It would be a small compromise to re-adjust the sails afterwards.

    Re my own build, I'm playing around with my equipment and improve where I thing it would be required, but mostly everything seems to go according to plan. Hopefully next year is going to be a better one than this one in this pathetic crime riddled cuntry :(

    So in good faith we're clinging in there - another aft mast may well be on the horizon...
    And with a bit of luck, and some other things it may well be the one to change some minds. I hate circumstances.
     
  8. CT 249
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    CT 249 Senior Member

    On the other hand, if people get into an event knowing that those who created it are reluctant to have them there, maybe they shouldn't be surprised if there is no acknowledgement.

    Every sport, indeed every human activity, has some boundaries. Whether it's bicycle racing, fencing, surfing, windsurfing, snow sports, rowing, kayaking, race walking, many forms of motor sport, the local Jane Austen appreciation society, the Blue Hills Birdwatching club or the GWR Trainspotters Guild, they all have certain rules about what you do and what you don't.

    Most people seem to handle it, as did most sailors. When organised dinghy racing started, they generally ran their own races. When canoes started racing in the 1800s, they made their own races. When small offshore boats started, they made their own races. When windsurfers started, they made their own races. When kitesailing started, they made their own races.

    Why on earth do mono events get so much grief for staying mono-only, when so many other activities are similarly restricted, and the events that DO allow all types in rarely seem to benefit much from it?

    My family's been into multis for three generations, and I married a Tornado worlds sailor, so I'm not anti-multi. But the ideas that multis have been picked on are a myth, just as the claim that Herreshoff's Amaryllis was banned from all racing is a complete and utter myth*. The idea that multis, unlike equipment in most other sports, somehow deserves to be given a start in every event is surely an attitude that's been setting back the type far more than any supposed bias ever did.

    * The simple historical truth is that many NY clubs of the time allowed cats to race - they just normally put them in their own class, just like they separated catboats from knockabouts, schooners from cutters, sloops from yawls etc. Many of the rich and powerful had cats, including several YC commodores including the founder of the NYYC itself. But people, for their own reasons, seem to prefer the "they hate us and always have" line.
     
  9. RHough
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    RHough Retro Dude

    You are 100% correct that NYYC did have cat classes while there was interest. (Thank you for many hours of reading to prove myself wrong on that, I used to be one of the people that believed NYYC banned cats.)

    You also have touched upon part of the problem from some multi-hullers. They have the "we are excluded unfairly" attitude and it can be self fulfilling.

    There is a difference between excluding multi's because mono's don't want them in the fleet and no multi's in the fleet because no multi's want to sail. Not allowing motorcycles to enter a bicycle race is one thing. Limiting entries in a motorcycle race to one type or brand is another. I don't know if there are many recumbent bikes that want to race, but if there are would it be better to give them class and make your event bigger and better or to exclude them solely because they are "different"?

    I think the face of sailing is changing. I think we will see more fast cruiser multi's and more interest in multi's in the future. If they decide to race they should be welcome, just as they were when NYYC ran classes for them.

    Randy
     
  10. michael pierzga
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    michael pierzga Senior Member

    Knock it off...Modern racing..regattas... are controlled my measurement rules so that race officials can somehow compare apples to oranges. How would they form a handicap rule to include Multi's or any non standard hull form ? How would you provide guidance to owners and designers wishing to build boats ? How would you protect the value of existing owners yachts . ?
     
  11. CT 249
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    CT 249 Senior Member

    Thanks for reading the NY cat scene stuff. Like you, I believe that the "we have always been excluded unfairly" stuff really hurts the multi scene. Where we differ is that I believe that any club still has the right to decide that it's not worth opening up their events to other equipment, without other people claiming discrimination.

    I don't agree that there is any comparison whatsoever between racism or sexism etc and excluding certain sorts of sports equipment from an event. In one there are divisions based on people themselves or their inherited characteristics, in the other there are divisions is based on the activity that people (of all types) chose to do. They are completely different things.

    Groups of people must surely have the right to voluntarily form a group that concentrates on one activity, as long as it allows in anyone who does that activity. And surely the group has the right to work out how narrowly they define that activity, whether it's as wide as "sailing" or as narrow as "Corsair trimaran sailing" or "racing in competitive A Class catamarans."

    By your definition, my local bicycle commuters activist group are akin to racists, because they don't have a section dedicated to car commuters. The dog-training club down the road is, by your definition, discriminating unfairly because they don't have a section for greyhound racing or cat fanciers. The labrador club is unfair because it doesn't have a section for fox terriers. The football club, by your standards, is discriminating because it doesn't have a gridiron team. The A Class cat association would have to run cruises for those who sail Hobie Waves, or be discriminating. It is obviously illogical, therefore, to say that all clubs or events MUST be all-inclusive.

    This is not excluding an activity merely because it's "different". It's excluding it because much of the reason to have a club or competition is to concentrate on certain activities. The dog training club just wouldn't work if it had to include greyhound racing and Burmese breeding. The A Class association's volunteer RCs don't have the time to run races for Waves. The Governor's Cup may not need to have to run another class, and it may detract from the enjoyment of those who made the event into something others want to join.

    Why in the world do we have sailing clubs at all? It's so people can concentrate on the sport of sailing, NOT basket weaving or kayaking or powerboating. It's not excluding people on who they are, but on what they chose to do for fun.

    Yes, combining very different equipment can work, but often it doesn't work or at least poses major issues that can reduce the enjoyment of those who created the event and are its backbone. As someone who sails many different types, it's interesting to see that it's not a person problem (there are great people on every side) but a perspective problem - things look different when seen from a different deck, and it's easy to start thinking that it's the other type of craft that is the problem, instead of perspective that's the problem. It CAN be managed in a way that strengthens a club or event, but it CAN be a significant problem, and for many events it's simply not worth it.

    Catering for different types of gear DOES often introduce logistical or safety issues. For example, at my local club one newer type of craft puts much higher demands on course layers and RCs than the traditional boats. What right does anyone have to come into an event and demand special treatment from volunteers? Allowing recumbent bikes into our races WOULD have very significant safety and logistical issues that would reduce the enjoyment of the club members as a whole. If recumbents want to race, fine - go what the founders of our club did and make a club (which is, of course, what they have done).

    Where you stop when you say "you must allow everything in". Does the Governor's Cup have to allow windsurfers? A Class cats? Kites? Optis? Macgregor 26 power sailers under motor? Stand Up Paddleboards?

    If a club decides that bringing in new groups is worth it, great. It often is. But IMHO there's a world of difference between allowing clubs to have free choice, and pressuring them to let you in and then insulting them afterwards as is often the case. The respect has to go both ways, and most of the time it doesn't seem to flow back from the faster craft to the slower ones. Going "woo hoo, we finished ahead of all the other type, they're slugs" is pretty silly when the other type competes under different rules - you could win the motorcycle GPs if you raced a F1 car, but no one would find the slightest sense in doing it.

    Things can also be different in an area where the activity is not all that popular and you need critical mass. But that's not the case where the Governor's Cup is held, or where I sail. And even in smaller areas, bringing in different types can destroy the fun for some people, because it changes the accent of the club.

    Look at your very own (as I understand it) port. One group felt so excluded by the change of accent in their club that they had to leave and form a new club. How is that fair to those who formed the first club and now have to form a new one?

    That's happened a fair bit around my place, mainly by yachties taking over dinghy clubs and effectively driving them out or marginalising them. All it does is reduce diversity and opportunity, which can often best be fostered by clubs and events that are closely targeted to one type of sailing AND by other events being open to all if that happens to suit those who did the bloody work and created the event!
     
  12. RHough
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    RHough Retro Dude

    I agree it is a case by case sort of thing. A sailing club is just that, a club who's members have a common interest - sailing. For the Pan-Am pre games we were faced with running three courses. Sailboards and Hobbies on the course I worked, Laser, Laser Radial, Laser Women, and Snipes on another course, and J-24's and Lightnings on the third course. It was a great three days.

    You are 100% correct that the support requirements differ for each class, with the sailboard/Hobbie course needing 9 marks. I am not saying that every club MUST set courses to fit a class's special needs, but if you have a course that CAN be shared, like most mono keelboat courses it makes no sense to exclude multi's just because they have more than one hull. The sailing that cruiser/racer types enjoy works for bigger multi's too.

    You some of this right:
    Multi sailors are sailors, they are not powerboaters, basket weavers, or kayackers. Why exclude fellow sailors?

    Multi sailors chose to sail, yet they are excluded from sailing clubs? I find that hard to defend. How is the enjoyment of sailing the boat you like diminished by someone sailing another type?

    I agree with the respect comments, but the fast guys in giant dinghy like "sports boats" are every bit as bad as multi-hullers. The 505 class used to claim they were "Overbearing in Victory, Obnoxious in Defeat", that attitude is not unique to multi-sailors. How are ULDB Sports Boats ok and mutli's not? Its okay for the old guard to put up with cheeky attitude from the ULDB guys because they aren't multi-hull sailors? That is anti-multi bigotry. Why didn't the keelboat faction just tell the sports boats guys to go start their own club?

    Did the Dinghy Club get taken over by "Yachties" or did many on the members move into bigger boats as they aged and wanted to keep the same circle of friends? That is how some of the clubs in the SF Bay area evolved.

    You sail more than one type of boat, do belong to several different clubs? Pay multiple dues? I can see not expecting your sailing club to hold bicycle races, or your bike club not running regattas. However it sounds like the recumbent bikes found a way to support their own races and YOUR club lost out on the dues and bar sales. If they are self supporting now, they would not have been a burden to your club and both groups now duplicate some resources that could have been shared ... that sounds short sighted to me.

    We are WAY off topic. :)
     
  13. RHough
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    RHough Retro Dude

    You confuse measurement rules with handicapping rules. None of what you say applies to performance based handicapping. Our handicapping committee can and does rate boats from 400 D/L cruisers to custom multi's. If you want to do it it can be done. It just is not as easy as picking a handicap number out of a book.
     
  14. michael pierzga
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    michael pierzga Senior Member

    That Handicap rule must be mighty complex !!!!! Even laying the course out must be a challenge.... I cant Imagine putting multi's in the same startline procedures as mono's. Yikes ! think of the smash ups.
    Ive got nothing against Multihulls, great boats...just apples and oranges on a race course. Even trying to find space for a gang of multi's at the club dock after the regatta for a quite little drink must be a challenge!
     

  15. brian eiland
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    brian eiland Senior Member

    Governor's Cup Race on Chesapeake Bay

    That is why the Governpr's Cup Race decided to give the multihull fleet, as an entity, its own start after there were enough of them inquiring as to entry into this fun race of the sunmmer (BIG party at the finish).

    The commitee made no attempt to handicap the boats against the monohulls, but rather let the multihulls handicap themselves against one another. And start them in the very last sequence so as to not interfer with the rest of the monohull fleet. Very good choice.

    http://www.smcm.edu/govcup/

    In June 1986, Yacht Racing and Cruising magazine (now Sailing World) ranked the Governor's Cup's day of celebration as one of the top ten post-race parties in the sailing world. In 1985, it called the Governor's Cup "the race that goes somewhere," and declared, "The race down the Bay, with its variable weather and currents, is an interesting one, and the enjoyable ambiance at the end of it provides a happy finale. The combination has made this increasingly popular event . . . a Bay Classic."

    I think that year there was close to 400 boats.

    BTW I was not complaining that we were discrimated against unfairly. Our crew aboard that Stiletto 30 were just disappointed that someone didn't mention the fact that we sailed thru the whole fleet of some pretty fast boats and ended up first out of 400 boats. Seems a little one-liner might have been appropriate.
     
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