Internet Info 1994 March

home *** CD-ROM | disk | FTP | other *** search

/ Internet Info 1994 March / Internet Info CD-ROM (Walnut Creek) (March 1994).iso / answers / rec / boats-faq / part1 < prev next >

Wrap

Text File | 1994-01-22 | 33.8 KB | 820 lines

Newsgroups: rec.boats,rec.answers,news.answers Path: bloom-beacon.mit.edu!nic.hookup.net!swrinde!cs.utexas.edu!uunet!brunix!jfh From: jfh@cs.brown.edu (John F. Hughes) Subject: rec.boats Frequently Asked Questions (Part 1 of 4) Message-ID: <boats-faq-1-759101010@cs.brown.edu> Followup-To: rec.boats Originator: jfh@euclid Sender: news@cs.brown.edu Reply-To: jfh@cs.brown.edu (John F. Hughes) Organization: Brown University Date: Thu, 20 Jan 1994 21:23:33 GMT Approved: news-answers-request@MIT.EDU Expires: Fri, 20 May 1994 04:00:00 GMT Lines: 803 Xref: bloom-beacon.mit.edu rec.boats:19228 rec.answers:3808 news.answers:14364 Posted-By: auto-faq 2.4 Archive-name: boats-faq/part1 Chapter 1 Pre-introduction The following is an FAQ for rec.boats. Next to each item in the table of contents is a symbol. A '+' means that I've answered it. A '-' means that someone else has promised to answer it. A ``0'' means that I intend to write it but have not gotten to it yet. A '*' means that someone else has provided it already. No mark at all indicates that I do not have the information to answer the question, but that no one has volunteered to provide it. In some cases, this means that I have written something to fill the gap, but it's not at all authoritative. This is especially true in the powerboating section. This document will be reposted about every three months. In addition, a copy will live at wilma.cs.brown.edu, available for anonymous ftp in the file rec.boats_FAQ.Z. Last posted: 10/14/93 This posting: 1/10/94 Chapter 2 Introduction I have been reading and saving selections from rec.boats for about 5 years, and operating various watercraft for far longer. I volunteered, in August 1992, to maintain this Frequently Asked Questions list for rec.boats, with help from many other people on topics where they know much more than I do. The contents of the posting below consist of the information sent to me by many people; only about 1/4 of it is my own writing. I am especially grateful to Michael Hughes (no relation) for providing much of the bibliography. If you have constructive comments please let me know. (I am John Hughes, jfh@cs.brown.edu). If you have additions you'd like to see, please let me know. The information in this posting comes in three forms. There are facts (addresses and phone numbers, etc.), generally accepted information (``How can I get into sailboat racing as a crew member?''), and opinions (``Is this magazine any good?''). Following a lead of Wayne Simpson, I've put the initials of the provider of the information or opinion in parentheses following the statement (e.g., (jfh)). There's a list of contributors at the bottom. Since I only started doing this *after* I had put together much of the list, a good deal of the information is unattributed, especially in the book reviews. I apologize to the original authors for this. By the way, my own bias is towards sailboating. This means that the powerboating information is scantier than the sailboating stuff. 2.1 TABLE OF CONTENTS + = provided by jfh * = provided by someone else = someone *ought* to provide it, but no volunteers arose Sailing stuff: * 3.1) What are the addresses of class associations for class XXX of sailboats? +* 3.2) How can I get into sailboat racing as a crew member? +* 3.3) Is the MacGregor 26 a good boat? It seems too good to be true. Does water ballast really work? + 3.4) What's a good first sailboat? * 3.5) How do those rating systems -- PHRF time-on-time, time-on-distance, Portsmouth, IOR -- and all that stuff work? * 3.6) Who/What is US Sailing, how do I join, should I join? * 3.7) Where can I find out about collegiate sailing? * 3.8) What about keels? * 3.9) Sailing simulators? * 3.10) Chartering and learn-to-sail schools * 3.11) Formula for hull speed based on length (and its limitations) * 3.12) Sailing in other countries. Powerboating stuff: 4.1) What is better? An I/O or an outboard? What's cheaper? + 4.2) Is the Bayliner a good boat? The price is great... + 4.3) Are Doel Fins a good thing? * 4.4) What is a Hole Shot? Will a Stainless prop add to my high end speed? + 4.5) Is VRO a good idea? * 4.6) What's a good first powerboat? * 4.7) Can I put unleaded gas in an old outboard? General Information: + 5.1) What are the addresses, phone numbers, 800 numbers, for suppliers of boating equipment? * 5.2) What organizations can help me learn about safe boating? + 5.3) Should I get GPS or Loran? + 5.4) What other newsgroups discuss boating stuff? * 5.5) What's the 800 number for the User Fee Sticker? +* 5.6) What's it cost to own a boat? * 5.7) Who can tell me about boat X? + 5.8) What are the laws about boats? Is there anything I have to get before I operate my boat? * 5.9) What's a formula for top speed, given lots of other info? * 5.10) How do find out what time it is, accurately, for navigation? * 5.11) Winter storage for batteries, and their state of charge. * 5.12) Online sources + 5.13) Should we split rec.boats? * 5.14) What sextant should I buy to practice with? * 5.15) Boat Pictures, and ftp sites for boat info. * 5.16) Propellor selection * 5.17) Binocular Selection + 6) List of Contributors Bibliography: * 7.1) Journals * 7.2) Nonfiction books about sailing trips * 7.3) Books about racing * 7.4) Books about maintenance * 7.5) Fiction about boats * 7.6) Books about design, seaworthiness, arts of the sailor * 7.7) Films/videos about sailing * 7.8) Misc Chapter 3 Sailing Stuff 3.1 Addresses of class associations for sailboats Here are some answers culled from the net. Laser mailing list: laser@cica.cica.indiana.edu signup: laser-request@cica.cica.indiana.edu or will@cica.indiana.edu Laser Class Association: ILCA 8466 N. Lockwood Ridge Road, Suite 328 Sarasota, FL 34243 Phone & FAX (813) 359-1384 Send them your name, sail number, type of boat, age, address, phone and $25 for a regular membership, $15 for junior (16 and under), $40 for family membership and list other people in family. J/24 612 Third Street Suite 4A Annapolis, MD 21403-3213 301-626-0240 (Steve Podlich or Cass Mairs) US Flying Dutchman Class (Official name is I.F.D.C.A.U.S - International FD Class Association of the US) Contact: Guido Bertocci 168 Overbrook Drive Freehold, NJ 07728 (908)303-8301 H (908)949-5869 B guido@blink.att.com Available info: General class info Promotional video - $14 Class membership $46/year INDIYRA International DN Ice Yachting Association Contact person changes from year to year, but you can always find out who's currently in charge by calling Gougeon Bros. Boats in Bay City, MI. Catalina 38 National Association Bill Huber 5076 Bordeau Ave. Irvine, CA 92714 Annual dues: $25 Catalina 36 National Association Garry Willis 4350 Glencoe Ave. Marina del Rey, CA 90292 Annual dues: $25 Catalina 34 National Association Jon Myers 10970 Seville Ct. Garden Grove, CA 92640 Annual dues: 1 year $20, 2 years $36 Catalina 30 National Association Doris Goodale 9141 Mahalo Dr. Huntington Beach, CA 92646 Annual dues: $15 $23 (Canada & Mexico; US funds) $24 (outside continent; US funds) Catalina 27 National Association Fred Rector 21 Lawrence Ave. Annapolis, MD 21403 Annual dues: $20 Catalina 25 National Association Christy Morgan 5011 Revere Ave., N.W. Massillon, OH 44646 Annual dues: $15 Catalina 22 National Association Joyce Seale P.O. Box 30368 Phoenix, AZ 85046-0368 (602) 971-4511 Annual dues: $25 Capri 22 National Association Dan Mattaran 888 Blvd of the Arts #204 Sarasota, FL 34346 Annual dues: $15 Coronado 15 National Association Ted Stoker 5157 El Roble Long Beach, CA 90815 Annual dues: $29 (sc) Capri 14.2 National Association Dave Dodell 10250 No. 92nd #210 Scottsdale, AZ 85258 Annual dues: $15 Capri 26 National Association Guy McCardle 529 Sycamore Circle Ridgeland, MS 39157 (sc) O'Day/CAL Boat owners association (email burati@apollo.hp.com for details) $18/yr - 6 newsletters, Boat/US discount, Organized rendezvous... Captains Log P.O. Box 684 Assonet, MA 02702 (mb) For owners of Catalina and Capri sailboats for which there is no national association listed above, contact Catalina Yachts, P.O. Box 989, Woodland Hills, CA 91367. Annual dues are 12.00 and include a one year subscription to MAINSHEET, the quarterly magazine of the Catalina and Capri owners associations. See also: The Sailing World ``Buyer's Guide'' and SAIL Magazine's ``Sailboat and Equipment Directory,'' and Cruising World, particularly for classes that are no longer being manufactured. All are available in many US libraries. 3.2 How can I get into sailboat racing as a crew member? The racers on the net seem to have a concensus on this (at least for crewing on large boats). Since I wrote this originally, I got the following words from mp, which seemed so relevant that I've put them first: ``you should add that if you want to get experience as neophyte crew, you need to show up consistently. Most owners can put up with you not knowing the ropes and would be willing to teach you what you need to know as long as they know you'll be there every week.'' (1) Go to local yacht clubs that have regular race series and post an index card on the bulletin board saying that you are new to racing, but would like a crew position. Give phone numbers where you can be reached, and put a date on the card so that people know it's active. (Ask the club steward about where to post the card, and whether it's OK). (2) Go hang out on the dock on whatever evening the local fleet races, and ask around if anyone knows of someone who needs crew. Come dressed for the occasion; bring a foul-weather suit if it's windy, and wear tennis shoes or boat shoes. Have a hat. If you bring other stuff (sweater, dry set of clothes) pack it in a small athletic bag or knapsack. Show up an hour before race time and let various people know you are there and available. The club steward, the launch boy/girl, and the dockmaster are all good choices. (3) Make it clear that you are serious--if the skipper says ``can you be there an hour before the race to help pack the 'chute?'', say ``Yes.'' Volunteer to help out with Spring work on the boat. If you have to miss a race on a boat on which you've been racing regularly, let the skipper know at least 3 days in advance. Let people know that you are willing to come out every single week to race. If not, word that you are unreliable will get around. (4) Listen and learn. Don't go aboard expecting to tell everyone everything you know. If it turns out that you know more than they do, keep quiet about it. Your quiet competence will eventually show through. 3.3 Is the MacGregor 26 a good boat? The MacGregor 26 has a very low price for a lot of boat. It also has a number of flaws. The equipment is not as tough as that on many other boats of comparable size, and the fiberglass construction is not as substantial either. If you are planning to do lake sailing on lakes of modest size, perhaps it is the boat for you. If you are planning on going into the ocean, perhaps it is not. The Mac26 is quite large for a trailerable boat, which is one of its big advantages. it uses water ballast, in part. It is more stable, even intially stable, with its tanks full than with them empty. See below. If you are considering a Mac26, you should also look at the Catalina 22. Compare the solidity of the structures, the hardware, the rigging, and also compare the resale values of similar boats in your area. Greg Fox has kindly written a short dissertation on water ballast, which summarizes the wisdom of the net on the subject (including at least one practicing naval architect). It really *is* correct, and you should read it carefully before you start disagreeing. Here it is: 3.3.1 Does water ballast work? Yes, but not nearly as well as a more dense ballast like lead. We are talking here about a fixed tank of water placed as low in the boat as possible and completely filled. An air bubble in the tank means that the some of the water is free to move to the low side and in this case stability can actually be worse than if the tank were left empty. If it is kept empty, the entire boat will float too high, reducing stability. So if your boat has a ballast tank, keep it *completely* filled while you are afloat. To answer the question in more detail, it needs to be broken down into two questions, one comparing water with lead ballast and another comparing water with no ballast. How does a water-ballasted boat compare with a lead-ballasted boat of the same length, beam, draft, freeboard and interior headroom, and the same weight of ballast? Water ballast is much lighter for trailering, as it can be drained. A water tank is cheaper than the same weight of solid lead. These benefits are purchased at a cost however. The water-ballasted boat will have less static stability, This is because the less dense ballast cannot be concentrated as low in the boat. The water-ballasted boat therefore cannot carry as much sail as the lead-ballasted boat, but will have similar resistance to motion. This means decreased speed. Also, this ballast occupying relatively high areas of the boat will require a deeper shaped hull for the same interior headroom which leads to a shorter (vertically) fin or centerboard for the same total draft. This adds up to worse windward performance. These are the costs of the more convenient trailering and lower expense. How does a water-ballasted boat compare with an unballasted boat of the same length, beam, draft, freeboard, and interior headroom? If designed to do so, water ballast could make a boat uncapsizable. At least, it will increase the capsize angle. Water ballast also adds mass and therefore easier motion in a sea and better way-carrying in a lull or a tack. It will do this for little increased expense and trailering weight. Basically, the advantages are bought at the cost of performance. A water-ballasted boat can carry little if any more sail than an unballasted boat. This is because it has little if any more stability at small angles of heel. However, for the same length, headroom, freeboard, etc. it must displace a greater amount of water equal to the tank of ballast. The same length, combined with greater displacement and no greater sail-carrying ability means less speed. Compared with an unballasted boat even more than compared with the lead-ballasted boat, the hull must be deeper, which again means less of the draft constraint can be allowed for the centerboard. This means poorer windward performance. Also the draft with centerboard up must be greater than the unballasted case. The better carrying of way and easier motion are at the cost of slower acceleration in puffs or after tacks. The increased mass is a double-edged sword. Why does it add little if any more stability at small angles of heel? Remember we are comparing a water-ballasted with an unballasted boat of the same length, freeboard, cabin headroom, etc. The increased weight of water must be put in an increased underwater volume of the hull located as low as possible. This added volume of water underneath what could have been the bottom of the unballasted boat has no net gravitational force under static conditions as long as it is completely submerged. That is, neglecting the additional weight of the tank and added hull material, the increased weight is exactly balanced by the buoyancy of the increased volume to hold it. It therefore can have no effect on either heeling or righting moment if the tank is full of water of the same density as that in which it is submerged. Another way to think of it is that the center of buoyancy is lowered by exactly the same amount as the center of gravity. Then how does it increase the capsize angle? At large angles of heel more or less of the water tank rises above the waterline. Now the relationship between the center of gravity and the inclined center of buoyancy becomes more favorable than the unballasted case. All of the weight of the water is no longer balanced by its buoyancy. Summary Could you make a SHORT summary of all this? Yes. Just consider a water-ballasted boat to be an unballasted boat but with improved capsize angle and all the plusses and minuses of added weight while afloat but not while trailering. There is a cost in performance. (gf) 3.4 What's a good first sailboat? The Sunfish and boats like it---very simple, easy to rig and to move around---make great learning boats for one or two people, but not for a family. The Laser is a tougher first boat, but there's likely to be a racing fleet nearby, and you can get an old one that's still plenty strong for very little money. My own belief is that a somewhat tired old boat is a good first one. It will teach you something about maintenance, and it will let you take some risks as you're learning---scratching an already-scratched hull is far more tolerable than scratching a brand-new one. In general, a boat that can be trailered and handled by one person is probably best; you'll sail lots more if you don't have to get a friend to help out. Sailing clubs can be a great way to learn. 3.5 How do those rating systems and all that stuff work? [ Contributed by Roy Smith ] PHRF (pronounced ``perf'') is Performance Handicap Racing Fleet. Unlike other rating systems (IOR, IMS, etc), PHRF ratings are not assigned based on some sort of measurement, but rather on past performance of similar boats. If you are racing in a club race or a local weekday evening or weekend series, where different kinds of boats race against each other, the odds are that PHRF is the rating system you're using. In PHRF, boats are assigned ratings in seconds per mile. Your rating is the number of seconds per mile your boat is supposedly slower than a theoretical boat which rates 0. Most boats you are likely to sail on rate somewhere in the range of about 50 to 250. All ratings are multiples of 3 seconds/mile (i.e. the next faster rating than 171 is 168). I think this is done as a recognition that the rating process just isn't accurate enough to justify rating boats to 1 second/mile resolution. Typically, a certain type of boat is given a stock rating based on past experience. Just to make it a bit more interesting, ratings vary somewhat depending on location; each YRA (Yacht Racing Association) can assign its own rating to a class of boat depending on their local experiences and conditions. For example, Western Long Island Sound, under the jurisdiction of YRA of LIS, is famous for light wind, which tends to give an advantage to certain types of boats, and YRA of LIS takes that into account when assigning ratings. On top of your regional stock rating, there are a variety of standard rating adjustments depending on how your boat is rigged. The standard PHRF rules allow you to have a 153 but take a rating penalty for it. Likewise, you can chose to not carry that big a sail and get a rating advantage. Having a non-standard keel, extra tall or short mast, a fixed prop (the stock ratings assume a folding or feathering prop), extra long or short spinnaker pole, etc, all result in rating changes. Some boats have several stock ratings for different common variations. For example, there are 4 configurations of J/29's; masthead or fractional rig and inboard or outboard. Once you've got your basic rating, adjusted for location and customizations you may have done, you still have the option of petitioning for a rating change based on whatever evidence you might care to present to prove that your rating is too fast (or the other guy's is too slow), an area that quickly gets into politics and boat lawyers. There are two flavors of PHRF, Time-on-Distance (TOD) and Time- on-Time (TOT). TOD is the more traditional and easier to understand, so let's start there. In TOD, you get a handicap equal to the length of the race course in nautical miles multiplied by your rating in seconds/mile. Thus, for a 6 mile race, a boat that rates 120 would get a 720 second handicap, i.e. her corrected finish time would be 720 seconds less than her actual time to complete the race. What people tend to do is think not so much about the actual rating, but rating differences, i.e. if you rate 120 and the other guy rates 111, he owes you 9 seconds per mile, so for a 6 mile race, as long as he finishes less than 54 seconds in front of you, you will correct over him and win. The other flavor of PHRF is Time-on-Time (TOT). In TOT, it's not the length of the race course that matters, it's the amount of time the race takes. To do TOT, first you have to convert your normal rating, R, in seconds per mile to a factor, F. The formula to convert R to F varies from place to place, but it's typically something like F = 600 / (480 + R). Actually, it's really something like F = 600 / ((600 - Rav) + R), where Rav is the average rating of all the boats in the fleet. Locally, we use an Rav of 120 which gives the formula with the 480 in the denominator. For reasonable values of R, you get an F which is a number close to 1. For example, a J/24 rating 171 has an F of 0.9217, while a Newport-41 rating 108 has an F of 1.020. To score the race, you take each boat's finish time, subtract their start time (giving their raw elapsed time) and multiply by their F, giving their Corrected Elapsed Time (CET). The theory behind TOT is that in a slow race (i.e. light wind), the boats tend to spread out but since the amount of time each boat owes the others is fixed by the length of the race course (in TOD), slow (i.e. light wind) races tend to favor the faster boats. On of the problems with TOT is that there is no universally accepted formula for converting R to F. With the sort of formula used above, you can argue about what should be used for Rav. What we do locally is use one Rav for the entire fleet, which is 8 divisions with ratings ranging from 36 to about 250 or so. Some people think we should calculate an Rav for each division, for example. Some people think TOT is a total crock and want to go back to TOD. Contributed by Stephen Bailey (sb) ] Sailboats racing under a ``handicap system'' have a function applied to their elapsed time, producing a ``corrected time,'' and the boats place in corrected time order. This function, which differs among systems, attempts to fairly represent speed differences among boats. There are two major handicapping philosophies: ``measurement'' rules which handicap based upon measurements, and ``rating'' rules which handicap based upon observed performance. The International Offshore Rule (IOR) is a measurement rule for racing boats. The IOR evolved from the Cruising Club of America (CCA) rule for racer/cruisers. The IOR concentrates on hull shape with length, beam, free board and girth measurements, foretriangle, mast and boom measurements, and stability with an inclination test. The IOR also identifies features which are dangerous or it can't fairly rate, and penalizes or prohibits them. The measurements and penalties are used to compute the handicap number which is an ``IOR length'' in feet. A typical IOR 40 footer (a ``one tonner'') has rating of 30.55 feet. In a handicapped race, the IOR length is used to compute a ``time allowance,'' in seconds per nautical mile (s/M) which is multiplied by the distance of the race, and subtracted from the boat's actual time, to compute the boat's corrected time. Longer IOR length gives a smaller time allowance. The IOR is also used to define ``level classes,'' where no time correction is used. Every boat in a class has an IOR number less than some number. The Ton Classes, (Mini Ton, 1/4 Ton, 1/2 Ton, 3/4 Ton, 1 Ton, and Two Ton), as well as 50-footer, ULDB 70 and Maxi classes are examples. To account for improvements in design and materials, boats are given an ``old age allowance'' which decreases their IOR length as time passes. In spite of the old age allowance, about 3/4 s/M/year on 40 footer, boats over several years old are usually not competitive, which is why IOR handicap racing is dead. Peculiarities of IOR designs result from features which increase actual performance more than they increase IOR length, or other odd rules; IOR hulls bulge at girth measurement points; a reverse transom moves a girth measurement point to a thicker part of the hull; waterline length is measured while floating upright, so large overhangs are used to increase waterline sailing at speed; the stability factor ignores crew, so IOR designers assume lots of live ballast; after the 1979 Fastnet race excessive tenderness was penalized; full length battens were prohibited to prevent main sail roach area, but short battens became strong enough that the IOR had to start measuring and penalizing extra main sail girth; main sail area adds less IOR length than jib area, so new IOR boats are fractionally rigged; The IOR encourages high free board, and high booms and prohibits keels wider at the bottom than at the top (bulbs). The Midget Offshore Racing Club Rule (MORC) is a measurement rule for racing boats no longer than 30 feet. The MORC rule is similar to the IOR. It computes a handicap length from various measurements, which is used to define level classes and derive time allowances. MORC seems to work better than IOR because the range of boats it attempts to handicap is not as large, and it is more quickly modified when problems arise. For example, the MORC recently adjusted their old age allowance to permit older boats to be competitive. The International Measurement System (IMS) is a measurement system intended for racer/cruisers. The IOR was not fair to racer/cruisers, so the Measurement Handicap System (MHS) was invented, in 1981, and accepted internationally, as the IMS in 1985. With a diverse collection of boats, relative performance varies not just with design, but also with race conditions. A 33 footer can beat a 40 footer upwind in moderate wind, but the 40 footer will probably come out ahead in heavier winds, or on a reach. The IMS uses a Velocity Prediction Program (VPP) to predict speed on different points of sail in different wind strengths. From the predictions, and the distance, course type and wind strength of a race, a time allowance is computed for each boat and subtracted from the boat's elapsed time to give corrected time. IMS rule designers believe the key to fairly handicapping diverse hull shapes is measuring a large number of points all over the hull and appendages, measuring sail area accurately, and using an inclination test (which is the same as the IOR). The VPP uses these measurements to account for heeling, crew on the rail, the immersed shape, and other factors. The IMS VPP doesn't yet account for dynamic drag of a boat pitching in waves, nor for appendage shapes which result in reduced drag. Some parameters are based upon incomplete experimental evidence. For example, the VPP predicts a greater benefit from full battens than is realized in practice. IMS defines a ``General Purpose Rating,'' which is a predicted time per mile around a particular course, in 10 knots of wind. A typical IMS 40 footer has a GPR around 595 s/M. The Performance Handicap Rating Factor (PHRF) is a subjective rating rule. PHRF was developed to handicap monohulls that didn't fit under the rubric of other handicap systems. It has since become the most popular handicapping system in the US, being almost universally used in club racing. PHRF assigns a boat a rating, in s/M, which is multiplied by the length of the course and subtracted from the boat's elapsed time to give corrected time. Ratings are assigned by a committee of the local racing authority, formed from representatives of the member clubs. The initial rating for a boat is based upon any information available, such as the boat's rating in another area, ratings under other handicap systems, information from the designer, ratings of similar boats, and a set of standard adjustments to basic ratings (e.g. fixed prop, extra large sails, etc.) All ratings are multiples of 3 s/M. For example, a J/24 rates around 171 s/M, and a J/35 around 69 s/M in many areas. Since ratings are assigned and administrated locally, they may account for local conditions. A good heavy air boat would rate faster in San Francisco Bay, than in Long Island Sound. A member may appeal a rating, presenting evidence, such as race results, which supports the appeal. The local committee's decision may be appealed to a committee of PHRF handicappers from all over the country. Although PHRF is subjective, it still attempts to rate the boat, in racing trim, with a perfect crew. Just because a boat never wins, or always wins doesn't mean its rating should or shouldn't be adjusted. Using this system, the slower the race, the smaller the percentage by which a faster boat must beat a slower boat. To correct this, some PHRF races are handicapped by multiplying a boat with rating R's elapsed time by (C / ((C - Rav) + R)), where Rav is the fleet's average rating, and C is a constant around 600-700, to compute corrected time. This system is called ``time on time'', the previous, more common, system is ``time on distance.'' The two systems only differ substantially when ratings span a large range (> 30 s/M), or races are long (in time). It is not clear which system is ultimately fairer. The Portsmouth Yardstick (PY) is a statistically based rating rule. The PY was developed by the Dixie Inland Yacht Racing Association to handicap any boat, including multihulls, which are excluded from all the previously described handicap systems, based on performance in races. The PY begins with a boat which is well sailed, and ubiquitous, called the ``Primary Yardstick.'' This boat is assigned a Portsmouth Number (PN), which is the time the boat takes to travel a fixed, but unspecified distance. In the US, the Thistle the primary yardstick, and its PN is 83. Elapsed times are collected for races. The fastest boat of each type in a race is assumed to have sailed a perfect race. The ratios of the fastest boat's time to the fastest yardstick boat's time, normalized by the yardstick boat's PN are averaged over all races to compute that boat's PN. Statistical techniques are used to discard outlying data points. A class with a large quantity of data, and no recent change in PN may become a ``Secondary Yardstick,'' used in the same fashion as the Primary Yardstick. The Laser and J/24 are examples of Secondary Yardsticks. The usual way to handicap with Portsmouth numbers is to multiply elapsed time by 100/(PN) to compute corrected time. This is a ``time on time'' system (see PHRF). In addition, PY has begun to compute numbers for different wind strengths. The Primary Yardstick is defined to have the same number for all wind strengths. Using these numbers, clubs can more fairly handicap races in various wind strengths. Since the PY data are not broken down by course type, it assumed that boats racing under the PY are racing courses similar to an Olympic, triangle or Gold Cup course. Below are formulas for converting among different system's ratings. Accuracy of these conversions may vary. PN = PHRF/6 + 55 PHRF = GPR - 550 PHRF = 2160/sqrt(IOR) - 198 Since we know that the IMS GPR is the time taken to cover a mile (of a particular course), in 10 knots of wind, we can estimate a boat's speed over this course given its PHRF rating: v = 3600 / (PHRF + 550) So, a J/24's (171 s/M) speed is 4.99 knots, a J/35's (69 s/m) is 5.81 knots. The J/35 is 16 of 3 s/m represents around a 0.4 Using the IOR conversion, a one tonner might rate 72 s/M, whereas they are actually much faster than that, rating around 54 s/M PHRF. This illustrates the ``advantage'' designers can take of the IOR. 3.6 Who/What is US Sailing, how do I join, should I join? United States Sailing Association (US Sailing), formerly USYRU, is the governing body for sailboat racing in the US. Its goals are to govern, promote, and represent sailboat racing and to promote the sport of sailing. Activities include sailing courses; certification of instructors, race officers, judges, etc; holding of various national championships; management of the olympic sailing team; and updating and publication of the International Yacht Racing Rules every four years. Basic membership is 35/year, but various discount programs are available through many yacht clubs. All active racing sailors should be members of US Sailing. (sc) The directory they provide has the addresses of every racing class known to man.