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Sailing Anarchy hade en bild på en Melges 30 med högre mast, djupare köl, längre peke och massor av folk för att håla paketet på rätt köl.

Några i min besättning tyckte att vi behövde ladda på lite mer segelyta… men jag tycker det ser ut som att vi har ganska ok med yta?

whopwhop-1

25 Comments

  1. Andres Jan 19, 2016 Reply

    Fathead & double backstays! :)

  2. boa Jan 19, 2016 Reply

    Despite ratings, sail area etc, I always had a question and it is still unsolved. What is better
    – more sail area and more people to hike it out (on a keelboat, meaning more total weight anyway)
    – or less sail area, and less people/total weight?
    For instance, X-99 with genoa#1 you might like to have 6-7 people total crew at 10-12 kts TWS. But if it would be a jib, Light/Medium, there would be enough of 4 people.
    What would be a trade-off between +8 sq.meters and ~270 kg to the performance of the boat?

    Before X-99, I sailed Vital26 (Inferno26), with modified keel – lighter for some 150 kg from original, also we took await genoa#1 of 22 meters, and had a jib of 16 meters. Our best results were ORC National champions overall and National Keelboat champions overall (out of 44 boats).
    Now on X-99 we are completely happy about genoa#1 and about the keel… But still don’t know what is better :)

    • Pelle Pedersen Jan 19, 2016 Reply

      Maybe an indicator is that the clasrules for X99 have a MAXlimit for crewweight!

    • Author
      Peter Gustafsson Jan 19, 2016 Reply

      Naturally it depends on the boat, course and conditions. And maybe the competition.

      As a general rule, for most boats, in mixed conditions/angles it’s faster with more crew. As “power” is sail-area in combination with righting moment, more of both is great (until something breaks).

      If you’re racing Transpac, ARC or other downwind point-to-point races it’s often faster with less crew/weight. Also if you know that the conditions will stay light.

      But I cant see that you would get a faster X-99 by reducing sail area along with crew weight. With maximum sail area you power up earlier (big difference in 2-3 knots of wind) and reach maximum speed earlier. You’re also able to carry the genoa further up through the register which will be beneficial in waves (and when the wind moves aft).

  3. boa Jan 19, 2016 Reply

    I see your point, Peter, but still – I would not like to be in sailing at 20kts with genoa#1 and say 8 people crew. it does not looks nice to me :-)
    In my opinion X99 is a light boat, and it should rather climb the wave instead of brake thru it. We have crew of 510 kgs, and I look at the jib at the winds of 16 kts already when beating.
    And we do sail against ORC club, not OD.

    • Pelle Pedersen Jan 19, 2016 Reply

      Question to you “boa”; why ask questions when you don´t accept the answers???
      I´m not a X99-sailor myself but from what I have seen and looking tuningguides they use genoa up to 20-22 kn of wind beacuse it´s the quickest way!!! And that was your question; what is best, more power or less weight?
      Obviously top X99-sailors has learnt how to manage the boat in winds up to 20-22 kn (with max crewweight) and still using the genoa…
      “Fast looks nice”!!!

    • Author
      Peter Gustafsson Jan 19, 2016 Reply

      Looking in the ORC database there’s X-99s with both the OD genoa and jib configuration. To compare those two with similar crew weight would give you an idea on how sail area affects performance. I just did a quick check to see that a genoa was considered to be 2.5% faster in 10 knots.

      On the J/111 I did an ORC-analysis with shorthanded crew (160 kg) vs full crew (720 kg). The light crew was marginally faster in light air but slower in most conditions. From 2% slower on a beam reach in 8 knots of wind up to 8% slower on TWA 135 in 20 knots (planing). 3% slower VMG in 10 knots and above. Average in all conditions/angles ~2% slower.

      For a better result you could do an ORC test run with your different configs, but from the two cases above it’s pretty clear that sail area is important to performance (duh) and the benefits of a lighter “package” are negated by weight on the rail.

      • Joakim Jan 19, 2016 Reply

        Note that ORC does not change sailing displacement while changing crew weight, thus it does not show the drag change due to weight change.

        From the ORC VPP Documentation:
        “The owner may accept the default calculated weight, but can declare any crew weight which shall be
        recorded in the certificate. The declared crew weight is used to compute increased righting moment
        while default crew weight will be used to compute sailing trim displacement.”

        • Author
          Peter Gustafsson Jan 19, 2016 Reply

          Ah…

          Are there any good reason why different weights are used for different calculations?

          Do you know if it’s possible to doi a VPP run with a specific default crew weight (ie getting better shorthanded performance numbers)?

          • Joakim Jan 19, 2016

            The reason is to have an always decreasing GPH with increasing CW and to increase the effect of CW to GPH. There used to be boats that got a higher GPH with lower CW. It’s not possible to change how the VPP uses CW, but you could play with real displacement and RM to get about the same.

          • Author
            Peter Gustafsson Jan 19, 2016

            To get a rating break for sailing with a smaller crew sounds like a good thing :-)

            So the VPP is only “correct” when declared = default crew weight. Above/below this changes in crew weight doesn’t affect drag or planing thresholds.

  4. srsseglaren Jan 19, 2016 Reply

    To be fair, the class jib is only 19,41 square meter compared to the max genua 30 square meter.
    If one should prefer using a jib instead of genua one could also change the spreaders to longer swept back spreaders with the top shrouds mounted out on the side of the hull and the lower shrouds monted closer to the cabin making room for a larger jib of 25 squaremeter.

    Depending on ambition one could uppdate the mast by raising the forstay, closing the differences even moore.

    • Author
      Peter Gustafsson Jan 19, 2016 Reply

      Why (I know I’m not supposed to ask that question)?

      The X-99 is a great design that works extremely well in typical Scandinavian conditions. Great bang ffor the buck in OD config.

      If you must have a jib I hear X-yachts did both a decent 35′ racer/cruiser and a sweet little 33′ with a sprit.

      ;-)

    • srsseglaren Jan 19, 2016 Reply

      Guessing the main reason for the boat choice would be running cost :-)
      Swept back spreaders would enabling losing the backstay fewer forsail´s simplyfing the boathandling

  5. JIMMY Jan 19, 2016 Reply

    Generally, for a displacement hull, if you add crew weight, that weight does not cause the wetted surface area to increase very much and so you don’t add that much drag. But the weight of the crew increases stability quite a bit (and therefore the boat´s sail carrying power), especially at small to moderate heeling angles, where the sail plan, hull, keel and rudder is most efficient, and in the end the extra power is in excess of the added drag.

  6. srsseglaren Jan 19, 2016 Reply

    Some inspiration of uppdating 30 year old boat´s, Ross 930 “Pepe”:
    https://www.youtube.com/watch?v=Pw2HsxZCQVk

    (Keen speeder´s should freeze the movie at 4.09)

  7. boa Jan 19, 2016 Reply

    sorry for mislead, esp. Pelle.
    I am not supposed to “not accept” the answers, all I wanted to do is to bring you the whole picture I have.
    And I am more to say in most comments: :-)
    – genoa on X-99. Acc class rules, there are only two dimensions limited – LPG (luff perpendicular) and JL (luff length). ORC requires 7 measurements to evaluate your genoa area. these 5 missing measurements cost some 2 sq.meters in the certificate.
    – fast looks nice, I agree. We had fathead on Baraka, and spinnaker of 62 sq.meter compared to 47 original, and lighter keel with T-shaped bulb. that was really fast some times, compared to age and size of the boat.
    – big genoa trade off and aft swept spreaders… There is Catalina 37 boat in Lithuania, couple of years ago they took away that massive genoa away, swept back spreaders, put fathead mainsail… footage here (reefed, as we too) https://www.youtube.com/watch?v=nhz2D6Y3iTs

    But let’s get back to the heading of the post – fathead, runners, and twice longer bowsprit, Peter?.. :-)

    • Jakob Jan 19, 2016 Reply

      My experience is that being at the maximum crew weight of 512kgs on the X-99 is essential. There is a huge difference between lets say 450 and 512 kgs. However maybe it is possible to change the sail design in order to accommodate 450kgs better.

      I wouldn’t be surprised if increasing the crew to 600 kg would make the boat even faster.

      • boa Jan 19, 2016 Reply

        it might be. I we would see videos from especially older times, we may see 7 people crew.
        When we talk ORC-wise, you may do whatever you like.
        Not too many years on X-99 in my experience, so I can not judge 100%, but the main problem is there is no good crew around – to work out on a boat and be available majority of the season.
        However, one reel thing is not to be a crew, but work (hike) as real crew.
        thanks for sharing your experience. I guess comments is good place to do so.

  8. Björn Svala Jan 20, 2016 Reply

    The only reason for being 7 people on a X-99 is the weight wich gives performance in the OD set up.
    The extra hands will not give you any advantage in my opinion but you will get a logistic problem on board with the extra person. And the benefits in medium to heavy wind will be much bigger than the small performance loss in light wind. At least thats my experience from almost 10 years of sailing as trimmer on SWE-532 Exilia.
    And yes it´s very important to be close to the max crew weight.
    Björn Svala

  9. boa Jan 21, 2016 Reply

    well noted.
    But let’s put it another way – Peter/Blur does not have max crew weight since it is not OD. How many crew would be considered as optimum? and again – if it is possibile to accomodate more crew onboard, maybe it is reasonable to add sail area the crew may hike out?
    I suspect it is more theoretical in terms of sailing region and conditions Blur usually does, but that was the discussion given, according the post name.

  10. Pelle Fälth Jan 21, 2016 Reply

    Kinder egg solution; a lot of sail area, a big crew and you can for a choir https://www.youtube.com/watch?v=BxGugjUXpJ8

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