Beating to Windward

Columbia and Patchogue are the two newest boats in the Trudeau line, and they continue the long tradition of style and performance that are a consistent trademark of Trudeau Yachts. There are lots of features about these boats to talk about, but today I wanted to focus on the reefing effects, and how they impact upwind performance of the boats.

Wind Engine. 

Before I can talk about reefing, I need to back up a bit and quickly remind people about the differences in wind engines in SL boats.

In real life, all sailboats see the same wind and are bound by the same basic laws of physics. That’s not necessarily true in Second Life however, where different vehicle wind scripts result in major performance differences. I discussed this a few months ago, noting that many popular boats in SL are powered by “true wind,” others by “apparent wind,” and still more by “something in-between.” Here’s a link to Mothgirl Dibou’s insightful discussion of this issue.

All Trudeau yachts over the past 18 months are based on an apparent wind engine initially introduced with the Trudeau Twenty. That basic design has been re-tuned and refined to match the specific characteristics of each new Trudeau vessel, and the underlying  Trudeau force algorithm is based on the same apparent wind equations skippers use in real-life.  Mastering these boats may prove a more realistic (and occasionally more frustrating) challenge to sailors, since the apparent wind speed (AWS) and the apparent wind angle (AWA) are constantly changing as the boat moves through the water. A skipper needs to ‘stay awake’ (just like Real Life!).

The chart below plots the “Speed Over Ground” (SOG) for six current Trudeau boats using optimal settings at a slow wind speed of 5.0 m/s. That slow wind speed makes it possible to get pretty accurate numbers for the different points of sail. It also gives a “baseline” performance estimate under conditions that don’t require reefing and cause relatively little heel.

With a 5.0 m/s breeze, Columbia (in Blue above) looks extremely similar to the J-Class (in Red). The boats come out of irons and start gaining momentum at around 38-40° AWA and achieve a  maximum upwind velocity at approximately 50° AWA.   Both boats (in fact all Trudeau boats) then exhibit a near-linear decay in performance response as the point-of-sail moves progressively downwind. (Columbia’s spinnaker effect is shown here. )

Patchogue’s wind response is shown in Purple above, and in Blue on a more detailed chart below.  On first look, Patch might seem the slowest of the whole Trudeau bunch.  For example, since a catboat has no headsail, Patchogue has a terrible time pointing upwind; at  40° AWA Patchogue is still luffing, with a flat ‘zero‘ boat speed despite optimal sail adjustments. The Patch only comes to life around 44° AWA, and it then quickly jumps to its peak SOG between 50°- 60° AWA.   That performance still doesn’t seem much to write home about, even if your skipper hikes to windward and optimally adjusts the centerboard.

 But let me tell you: What I just said about Patch with wind speed= 5.0 m/s is far from the whole story; I mean first looks are often deceiving.  Far from being a slowpoke, Patchogue may actually be the fastest Trudeau since the Beach Cat once the wind speed  picks up. Reefing  is one of the reasons.

 Reefing

In real-life sailing, with increasing wind speed a boat accelerates and begins to heel due to apparent wind forces.  A wise skipper will often decide to ‘shorten sail’ under those circumstances. Taking down a sail or reducing the mainsail size by setting a reef point makes a boat more stable and easier to manage, while also reducing the risk of a capsize. Columbia and Patchogue emulate these effects by incorporating  reefing options that enhance the boat’s performance. Columbia has two reef positions; Reef One douses the top sails and  gives the boat a significant speed boost when winds are over 11 m/s AWS.  Reef Two is effective when the wind exceeds 13 AWS; it shortens the main and boosts boat speed performance even further.

The chart below shows these reefing effects in Columbia using a windsetter Real Wind speed (RWS) of 11.0 m/s. The Red curve shows the boat’s baseline performance without reefing. The maximum boatspeed occurs between 60°- 70° and is roughly 80% of true wind.  Not terrible, but nothing to write home about.

Sailing upwind with the windsetter’s 11 m/s RWS, the boat’s  apparent wind speed quickly jumps into the range where reefing is effective.  As shown in green in the chart below, adding Reef One greatly enhances boat performance on a close haul or close reach, yielding a maximum boatspeed equal to true wind at approximately 50° AWA.

If that’s not fast enough for you, Columbia’s got more; it’s got Reef Two, as shown by the Blue curve below.   In fact, Reef Two provides a truly explosive performance boost; at 40° AWA Columbia generates a boatspeed that is nearly four times the unreefed response and 40% faster than True Wind, and Patchogue’s Reef effects are similarly prodigious. Woots!

   

True and Apparent Wind Angles

If the huge Reef Two boost that I just described in Columbia and Patchogue has you excited, and you’re starting to dream about using it to blow everyone away on the the racecourse… please take off your sailing gloves for another minute so I can tell you the “downside.” Reef Two will make your boat go explosively fast, but “Never confuse movement with progress.”You pay a price for that speed boost.

 Since Trudeau boats are powered by apparent wind, as the boatspeed increases the apparent wind angle shifts toward the bow of the boat (due to the increased headwind) . If the windsetter is set for 11.0 m/s and a Columbia skipper tries to sail a heading of 40° AWA without reefing, as the boat speeds up the  corresponding Real Wind Angle (RWA) will settle in around 55°. Thats not so bad, although it probably means it will take a few extra tacks to reach the upwind mark. It’s hard to complain too much though, since the same problem occurs in real sailing.

 If a skipper now adds Reef One, the boat strongly accelerates, swinging  the apparent wind angle further forward. in order to maintain a 40° AWA heading, Columbia needs to sail a real wind heading of 75°. That angle means it could take a skipper twice as many tacks to make it upwind. 

Now comes the “killer.”  Under the same conditions if a skipper decides its taking too long to continuously zig-zag the way upwind and wants to go faster she can push the button labeled ‘Reef Two.‘ As shown by the chart above, Reef Two  produces a major surge in boatspeed at 40° AWA. unfortunately, to keep that heading a sailor will need to fall off the wind again… this time to a real wind heading of 92° at best.  That course is actually perpendicular to the upwind target. 

In case you find these numbers confusing, here is the bottom line: If a skipper is trying to reach a mark directly upwind, a Real Wind heading over 90° will never get you there.

Startline Tsurus.

Let me give you a practical example of this problem using the Blake Sea- Atlantic raceline. The default wind there is ‘spd 11.3 m/s, dir 170‘ and nearly perpendicular to the raceline, but with a 10°port-start bias.  Many racelines are similar. These default wind settings are actually pretty great for Real Wind boats like the Tako or ACA33. As evidence, here’s an overhead image from last evening, showing an ACA33 fleet crossing the start line.  The generous polar and lack of apparent wind effects allows most ACA boats to do a ‘point and shoot’ start, where a skipper sets a Real Wind angle of  25- 30°  and then sprints as fast as possible in a straight line over the Start. (Closing your eyes helps 🙂 )

 Pity the lowly Patchogue, however. 🙂 

Even starting from far back and over a sim away, as the Patch accelerates on a heading of 44° AWA towards the start line the apparent wind rotates toward the bow, and with Reef Two the real wind angle slides over 90°. Patchogue therefore slips past the raceline at high speed… and never crosses it.   

This turns out to be a particular problem at the Atlantic reaceline, since the windsetter default angle is 170° and there’s currently a committee boat ‘barging barrier’ in place at the Starboard end of the line. A Columbia or Patchogue skipper that is willing to underpower the boat just enough to make it across the Start will end up coming in nearly parallel to the raceline… and I know I am stubborn, but… I’ve yet to make it across the Atlantic raceline in a Columbia or a Patch without slamming headlong into that committee boat or the observation tower.  

Based on the above discussion, the little diagram below shows why. Real Wind boats can cut the line at a real wind angle optimum for their polar; In the Tako, that’s 35°. In Columbia or Patchogue, the approach angle is determined by the Reef setting and AWA.  As shown below, without a Reef Columbia can cross the line with a 55° RWA but has little momentum. With Reef One engaged, the boat can come in at a fairly extreme 75°  RWA, and with luck maybe get across.

 However, using Reef Two, the boat has to approach the line from the wrong side at an obtuse angle over 90°, and then gybe to port in the middle of the starting fleet in order to cross the raceline. And that’s assuming the skipper didn’t first splatter Awlgrip and gelcoat all over the stern of the committee boat just trying to get there.    

 

 OK, What’s the Fix?

 I think there are several possible fixes  for this problem.

  1. The easiest solution is to lower the windspeed for races involving Patchogue or Columbia. Spd= 9.0 m/s does not push the apparent wind angle over 90°  and should allow these boats to sail as part of  One Design or Big Boat fleets.
  2. Another possible option is to ask skippers racing these two boats to only use Reef One. They may go slower, but they will be happier.
  3. The real solution however, is probably to reconsider the polars for these boats, or at least revise the size and profile of the ‘speed boost’ caused by Reefing. Trudeau boats already have a upwind boost built into the unreefed polar, and the selective extra upwind boost provided by the two reef settings makes that rather extreme.  Let’s see what J Trudeau comes up with!

Having said all the above, I have to admit Patchogue is becoming my favorite boat to race and cruise… Given the number of races for this boat Now scheduled by Waypoint, Triumphal, Mango and Fishers Island Clubs, it looks like a lot of sailors agree!

10 responses to “Beating to Windward

  1. Hello, newbie here but with some experience in other worlds.
    Very well documented article despite some inconsistencies and lots of numbers a bit confusing.
    Some questions please:
    1. Are the problems described here apply to other Trudeau as the Twenty or LeetleCat?
    2. What is the best purchase you recommend for this type of boat?
    3. How to learn more about the racing rules in use, boats, sports events?
    4. After reading the article, it appears that the boats are not tested before being put on the market, but maybe I am wrong. It would surely desirable that people like you can intervene before marketing as beta testers. What do you think?
    5. Where to find more boat tests?
    Thank you

    • Hi Rita! Thank you for the great questions!
      I think Chaos and Naeve probably already hit the high points, but let me give this a try too.

      1. Are the problems described here apply to other Trudeau as the Twenty or LeetleCat?
      Ans: As far as I can tell, this is a problem only in Columbia and Patchogue; here’s why:
      The Apparent Wind that powers a sailboat is a combination of the “Real Wind” and the “Headwind” the boat generates as it moves though the water. I’ve looked at all the current Trudeau boats over the past few years…
      For example, Trudeau TWENTY is a beamy little full-keel boat, modeled after the real-life Herreshoff 12 1/2. It’s not very efficient, and a Real Wind of 11.0 m/s will generate a boatspeed around 3.7 m/s at 50° AWA. Reefing gives the boat a nice boost to around 6.42 m/s, which is still quite a bit less than the Real Wind. That means TWENTY never generates a big enough speed boost to produce the kind of problem I discussed with Patchogue and Columbia.
      I initially thought J-Class might have “the problem” too, since its unreefed polar looks very similar to Columbia. However, J-Class only has ONE reef point, so it never gets into Reef Two overdose trouble. It’s one of those rare cases in life where “Less is More,” I guess.

      2. What is the best purchase you recommend for this type of boat?
      Ans: Asking what kind of boat a person should buy is like asking who you should marry… although I admit it’s a more serious decision and you’ll probably end up living with the boat a lot longer.
      There’s a wide variety of wonderful vessels in SL designed by a host of great shipwrights. If you are new to SLSailing I’d suggest you join a club, meet the 2,000 sailors who are now your best friends, take some free lessons, and start sailing. What should you sail? Grin… start with copies of all the GREAT free sailboats that are offerred at all the marinas; I’ll give you a list with landmarks and descriptions. However:
      Please don’t make the mistake to think: “If that boat’s free, it can’t be any good” 🙂 . Truly wonderful boats are now free to use, race, or own in Second Life Sailing.
      I admit though… free candy often comes at a hidden cost… Sometimes I worry that giving away free wonderous boats could be irresponsible. I mean, most people who start out with the free boats aren’t prepared and can’t handle it; they seem to quickly become hopelessly addicted, buying all the boats they can find, in every available color.
      Frankly, its sad seeing the long lines of sailors patiently queued up for hours before each new boat launching…
      Their hands shake and their palms sweat as they furtively trade whispers about the latest beta test rumor or they exchange tall tales garnered from past launchings…
      Rita, you may think you are strong, and that you will ‘just use the boats on weekends’ and in moderation… but Rita? It’s a slippery slope, and I fear before too long you’ll find yourself in that same line of salt encrusted sailhands there waiting on the dock, wearing an old Surfwidow Beaumont Sail Jacket smeared with Cetol and bottom paint, furtively toking on a soon-to-be-illegal “Reefer Two” while talking trash and waiting for the word from “The Man” (which in this case is that Trudeau Lady wearing the Keds sneakers).

      When that happens Rita (and we all know it will…) look up from your place in line. I’m that person in the torn J-Class teeshirt and the broken glasses standing in front of you.
      (Grin: IM me in SL and we can share a boat fix (cough); I mean trade HUDs…)
      xxx

  2. Hey Jane, again thanks for the interesting information. I had the ‘feeling’ that for these two boats performance can vary a lot, depending on more factors than what can be observed with other boats. These are more ‘complex’ boats… and in this case complex means interesting, less predictable. My initial, not-too-technical evaluation based on feeling more than measurements, was that on both these two boats performance changes much with different wind conditions and whether crew is active, passive or absent. For example, having active crew means the boat can be better balanced, allowing reef-1 to be used where reef-2 would be needed in a single manned boat to avoid excessive heeling.

    • Bunnie said: “… My initial, not-too-technical evaluation based on feeling more than measurements, was that on both these two boats performance changes much with different wind conditions and whether crew is active, passive or absent. …”
      Woots no kidding… For me, Patchogue is the bigger problem of the two boats to figure out. I appreciate Patch has unique and marvelous features such as skipper weight balancing and multi-crew hiking, but there are other issues with it that I’m still trying to grapple with.
      The lousy performance and terrible upwind response in light winds (5.0m/s) would make a Tradewind skipper wince…
      But then you get a slight rise in the breeze and the boat takes off… and accelerates… and KEEPS ACCELERATING…. until its jumping over the swells at nearly 150% of Real Wind.
      WOOTS!
      I admit I still do not have reliable polars on Patch with 11.0 m/s wind;
      Frankly, I run out of water in Blake Sea before this boat settles down!

      🙂 If my comments here sound in any way like complaints… wowzers, they are definately not.
      I’m with Orca, Taku, and Isis…
      I’m getting hooked on this boat!
      It’s a real challenge, yes, but I admit I can’t stop sailing it!
      It’s pretty fascinating!

  3. Hi, Rita. Welcome to SL sailing.

    To answer some of your questions:

    1. Are the problems described here apply to other Trudeau as the Twenty or LeetleCat?

    As far as I know, the Twenty and LeetleCat do not have the same reefing options. I believe that the J-Class, Patchogue and Columbia are the only ones with reefing abilities and the J-Class only goes up to Reef-1, so it does not experience the same problem that Jane described.

    2. What is the best purchase you recommend for this type of boat?

    If by “type” you mean a boat that reefs, you really only have a choice between the Patchogue and the J-Class/Columbia. The latter boats are grand replicas of America’s Cup yachts of the past. The former is more like a cruising day sailor. In general, you would expect different purposes for these boats.

    If your intent is to race, you may want to look at the calendar of events that are announced on the SL Sailing Association group to see which boat classes are most popular during your online times.

    3. How to learn more about the racing rules in use, boats, sports events?

    The forums at slsailing.org would be a good spot for SL-specific issues and conventions. If you want to learn more about the RL rules, check out the Racing Rules of Sailing at http://www.sailing.org/rrs.

    4. After reading the article, it appears that the boats are not tested before being put on the market, but maybe I am wrong. It would surely desirable that people like you can intervene before marketing as beta testers. What do you think?

    The boats were tested. I doubt they were tested in the extreme of race conditions in wind that’s favourable to much larger boats. As Jane mentioned, if the wind speed is dropped a little, the problem doesn’t exist.

    In real numbers, we’re talking about a shift from 11 m/s to 9 m/s. That’s going from a 21.4 knot (24.6 mph) wind to a 17.5 knot (20.1 mph) wind.

    5. Where to find more boat tests?

    This site is one of the best places to find boat tests for SL boats. Jane is a magnet for boat tests, whether by her own hand or by other contributors.

  4. Chaos Mandelbrot

    >>1. Are the problems described here apply to other Trudeau as the Twenty or LeetleCat?

    >As far as I know, the Twenty and LeetleCat do not have the same reefing options.
    –snip–
    Twenty and Knockabout have two reef points, the Leetle Cat one Reef. However they are not as fast as the J-class, Columbia or patch so they don’t have the issues Jane lists. Nor are, to the best of my knowledge, routinely raced.

    2. What is the best purchase you recommend for this type of boat?

    If by “type” you mean a boat that reefs, you really only have a choice between the Patchogue and the J-Class/Columbia.

    My personal recommendation for cruising is the Twenty. The iron spinnaker comes in handy in some sims. I would recommend patch if you want the performance. It is just more versatile.

  5. WOWzers!
    Thanks for this truly great and insightful article, Jane. Now I know why I never use reef 2 😉

    @ Chaos:
    Just FYI I started PHRF races for Leetle, Twenty and Knock at Triumphal. We’re racing the TrYC ‘Short Course A’ every tuesday at 10 AM … which may be a tad early for most US based sailors.

  6. edit:
    Just swapped the 10 am timeslot for 1 pm, hopefully it’s more convinient now and will draw bigger crowds.

  7. Umm…I’ve done over 18 M/s in a twenty upwind with a tws of 12 so yeah – it can happen, never tried it in a knockabout but I don’t see why it shouldn’t be capable of the same thing. A leetle cat has 1 reef point (as mentioned previously).
    Personally, apart from the occasional bizzarre speed you can get, which I’ve never seen as worth the time it takes to build up to it in a race and has all the accuracy of a shotgun blast so you tend to loose even more time adjusting for the next mark

    I usually work the boats to best VMG which is surprisingly consistant for the Columbia and J-Class and very different for the catboats (leetle cat and patchouge)

  8. It seems the Atlantic line has a light port bias with it’s default wind setting.. 🙂

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