Nothing will beat having some practice with an expert on board. Even designating a observer to start taking measurements and notes is a great start.
For me there is four things to fiddle with. 1) rate of turn, could be considered the radius of the arc of the turn 2) shape of the arc 3) when the jib is released and how it comes across 4) sail trim and point coming out of the turn For (1) generally the less time the boat is not powered up the better. It has to be balanced with too much rudder acting as a brake, or using up some of the kinetic energy to climb towards the mark. (2) and (3) is were the skipper can be creative and gain some ground on tacks. A common technique is to come up to head to wind, which hopefully is pointing right at the windward mark, and coast up for a short distance. Works well in lighter winds and flat water. A modification is were you can pinch up a while first and see how long you can sail under some power. I can sometimes get a few boat lengths as high as 25 - 28 degrees apparent before I lose too much speed. Note that there is some interaction here, as the boat slows down the apparent shifts back a bit. So where you may have been pointing at 45 TWA and 32 AWA as you slow down you may get 28 AWA but 39 TWA. Here is were a tactician looking at VMG can advise if it is helping or not. In one case, mirror flat water and no shear I pinched heavily on a lift and managed to take a useful increase in VMG while the lift persisted. When coasting up you may want to hold the jib back from tacking, barely cross the wind to get just a hint of backwind, and hold it there for a boat length or so. The thing you do not want to do is to release the jib and have a few hundred sq. feet of sail hung up on the shrouds / mast acting as a brake. When the jib starts to back wind much it will turn the boat for you and save using the rudder. (4) is by far the most critical area to practice. I see the general technique of falling off a bit after a tack to build speed, then coming up as velocity builds. It works, and helps a lot in a race. It may not be optimal depending on the boat and sails. Again, because boat speed is down the apparent has gone back a bit. Also, with racer / cruisers that do not point above 45 TWA every degree fallen off is a bigger distance to the mark. 5 extra degrees, from 45 TWA to 50 TWA hurts a lot more that dropping from 40 TWA to 45 TWA. A different technique is to use some of the energy to coast up, then complete the tack but stay up. During the tack the crew gets to the low side to help out, moves the jib car slightly forward. The main trimmer ( maybe ) eases the outhaul and the backstay. Make sure the main does not get trimmed up too aggressively before the jib is flowing, need to keep the rudder straight and the boat balanced. With the extra depth in the sails trim in for power but keep the boat pointing close to normal. Let the boat speed build, then start tightening the backstay first to maintain point as the apparent shifts forward. Then adjust the jib car, and finally the outhaul as speed returns to normal. The concept is adding some depth to the sail but staying closer to correct course may work better that having flat ( over trimmed ) sails and falling off. Depends on the boat and the sails. > On the genoa, the issue is > how to get the new sheet in as far as possible as fast as possible to > minimize grinding on the new tack. When double handing in normal wind and wave conditions we prep for a tack by centering the main traveler ( easing the boom away from windward ) a second before the tack or as the tack has started. With the other hand I take the jib sheet off the clam cleat and pass it back to the helms person. The lee side jib car has already been adjusted forward, and as soon as the jib sheet is released helm eases the backstay. As we tack over I start tailing the new jib sheet in, and helm is ready to steer down if required to clear the jib past the shrouds. I switch to using the winch as pressure builds and pass the sheet back to helm for tailing. As soon as we have the jib flowing I pull the main up a bit on the traveler, then go back to trimming in the jib. One thing that helps is the ARCO 40 winches I have are 1:1 on the direct side, so I can get a lot of sheet in quickly. When the sail is loaded helm may pinch up for a couple of seconds to help out while I am still 1:1. Note that we are not falling off much to build speed, which does work but tends to load the jib a lot more. From there on it is trimming as we build speed. > When it is blowing over 10, it is > really hard to pull the traveller up each time. Try easing the main sheet out, letting the vang off slightly to get some twist and then adjust the traveler. Finish off by tightening the main sheet. On my C&C 30-1 I switched to the Harken big boat track and car, have two single blocks separate location on the boom, a 4:1 main sheet with an additional 4:1 tweaker. Overall the best mod I have done for solo or double handed. Even with a good captive ball track and 4:1 on the traveler it is a stiff adjustment at 14+ knots. The tweaker is much better. I find trying to keep the boom close to centerline but allowing it to rise using the vang and main sheet keeps the boat balanced. A tight main sheet and vang, dropping the traveler is more common way but as soon as the boom is significantly off center as opposed to twisted I lose speed. Hopefully some points to think about, but having an expert on board even for a couple of practices is the way to go. Michael Brown Windburn C&C 30-1 Date: Wed, 25 Jun 2014 10:58:43 -0400 From: Tim Goodyear <timg...@gmail.com> To: David Knecht <davidakne...@gmail.com>, "cnc-list@cnc-list.com" <cnc-list@cnc-list.com> Subject: Re: Stus-List Tacking the genoa Message-ID: <cac9qattefvt6ch7x8mw398kcjjkyx-ddpdnabgzqh71vlju...@mail.gmail.com> Content-Type: text/plain; charset="utf-8" Dave, I agree with Charlie on the slow turns - as long as it doesn't stop the boat too much. Our fully crewed racing tack would be to start the turn slowly to gain height, then a slightly faster turn into the new tack, but modifying that for shorthanded would be faster and is what we do when cruising (trying to eliminate the grinding). On the main, it sounds like you need to work on your traveler or purchase system - there should be no need to use a winch in any wind strength. Ideal main trim is to pull the traveler to windward as you start the turn (helps turn the boat to windward), then build speed with the traveler to leeward on the new tack and gradually bring the boom to centerline as you accelerate. That should be no issue at all for your trimmer with a nice new Harken traveler setup... Tim Mojito C&C 35-3 Branford, CT On Wed, Jun 25, 2014 at 10:13 AM, David Knecht via CnC-List < cnc-list@cnc-list.com> wrote: > I would like to get some tips on race tacking. On the genoa, the issue is > how to get the new sheet in as far as possible as fast as possible to > minimize grinding on the new tack. I am usually shorthanded, which makes > this especially challenging. Doing some reading, I realize that I have > been releasing the old sheet too soon (when it first starts to luff as > opposed to when it is backwinded about 50%). What I am wondering is how to > steer through the turn. It seems like you might like to slow the turn > after the sheet is released to allow time for the trimmer to get as much > sheet in as possible before the sail fills and becomes impossible to trim > by hand making for more grinding. True? Any other tricks welcome. > Also, is it expected that you will nearly always have to pull the > traveller up to windward on each tack? I get a substantial amount of > backwind bubble in the main if I don?t. When it is blowing over 10, it is > really hard to pull the traveller up each time. Do people expect to do > this? Would you do it before the tack when it is easier or after? I find > it really hard to pull the traveller up when it is blowing over 10. Is it > expected that you might need to use a winch? > Thanks- Dave > > Aries > 1990 C&C 34+ > New London, CT
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