Model Yachting Newsletter: Issue 4a – March 1981

model nga yachting newsletter masthead This issue is the last in the current year’s subscription and enclosed you will find a renewal form. We hope you will support us next year, and to exnlain the adjustments in pricing we ask you to consider the following points:TWENTY FOUR PAGES PER ISSUE NOW STANDARD GOOD PHOTOGRAPH REPRODUCTION AND MORE OF THEM PLANS SERVICE STARTING NEXT ISSUE MAILED FIRST CLASS TO YOUR DOOR Printing costs for the next issue will be double the first one and postal rates have just gone up again! We try to balance the copy as much as possible over the year, this, and welcome your views on Twenty percent of our readers are from overseas countries and we do try to keep them in mind when editing race reports etce, subs Subscriptions for the new year run from JUNE 1981 1981/2 subscription is to MARCH 1982, £4.00 post paid U.K. £5200 post paid EUROPE. £6.00 post paid ALL OTHER COUNTRIES. We have full sets of 1980/1 copies still in stock and will supply these at the reduced rate of £2.00 per set (whilst stocks last) if ordered with a new subscription. adverts We accept advertisements from known bona~fide model yacht fitting makers who assist us to finance the Newsletter by this means and in turn we hope to heln people new to the hobby to find out where to get those awkward bits and pieces that the local model shop never stocks. If you wish to place an advertisement to sell quantity production of hulls, sails, or fittings, please contact the Editor to discuss direct (MALDON 740149). The advertisements for sale of secondhand boats etc. are put in free for subscribers. photos For both the Newsletter and the M.Y.A. exhibition stands we would like td receive good cnet | photos (black and white only for M.Y.N.) or slide negatives (colour for M.Y.A. stands). Anything different, fittings, sails, boats sailing, unusual shots of people etc., All will be acknowledged and-returned where requested. cover pic The cover for issue 4 was provided by Chris Williams and showed three local R.M. Class at Chelmsford, not on the North Sea as sugzested by one or two readers? This issue has a collection of boats which Model Boats magazine thinks have become extinct, the 6—metre, and also features a group of competitors at a National Championship all smiling and enjoying themselves!! The Editor is fifth from the right, so you all know who to give your money to when you see him, K827 is the scaled down John Lewis design “Kubernetes” which is used with radio as well as vane control for fun sailing. 10 rater review years, mostly ABOUT THE AUTHOR. Denis Hardwicke has been sailing model yachts for many 10Rater and A Class, and is an associate of John lewis and Denis Llippett. He was Chaiman of the M.Y.A. Council in the 1960’s and was on the committee that revised the 10Rater rule! The modern ten rater was basically evolved from three separate and Chronologically; Witty resurrected the fin and bulb concept in the in the early sixties: Synthetic sailcloth appeared and was adopted and Roger Stollery achieved a resounding success with “Warlord” in wingmast of considerable area and efficiency. identifiable happenings. 10R design “Excalibur”, by model yachtsmen, 1966 fitted with a Following the success of “Warlord”, the M.Y.A. locked the stable door by requiring that future rigid aerofoil masts should have their area added to the measured sail area. This was only partly successful in wntrolling unmeasured sail plan, for with the new designs of Witty, Hollom, lewis and others, giving better stability with fin and bulb layouts, mainsail roaches increased and, with roaches in excess of six inches, gave unmeasured areas in excess of two hundred and fifty square inches. During 1969 an M.Y.A. sub-committee was formed and an endeavour was made to rationalize the situation. At the A.G.M. of that year a revised formula proposed that all area in the vertical plane including that of a fixed round mast should be measured and that the boom and the hoist of the spinnaker should be established within a spinnaker area of 1¢4 times the sail area less that area of the mainsail. The constant was changed from 6500 to 7500. A broad generalization indicates the move in design from the early sixties. Ten Raters at that time weighed about thirtyfive pounds and carried about 1180 square inches on a water line of about fiftyfive inches. Displacements dropped to thirty pounds, sail areas went to 1080 square inches and water lines to sixty inches in the late sixties and, under the old formla, were then actually carrying about 1300 square inches of total area. Within a year or two after the formula change, displacement again dropped, about five pounds to twenty – twentyfive pounds, sail area to 1000 square inches and water lines went up five inches to sixtyfive inches. Typically, from Lewis’s “Sirocco” (35: 54: 1200:), Stollery’s “Warlord” (28: 60: 1083:), Dicks’ “Shallah” (23: 64: 1170), back to Lewis’s “Symergy” (22: 65: 1153:). Historically, that, roughly, was that except that Roger Stollery slipped in “Roundabout” (19: 60: 1250:) which has created a fair amount of mayhem during the Nationals of the last ten years in the guise of “Mr. Rusty”. National entries ran at about twenty – twentyfive boats year after year. In 1977 at the Brighton event, with winds sometimes in excess of twenty knots, about thirtyfive percent of the entry were damaged, some severely. From that point, interest seemed to wane; many clubs, both North and South, withdrew races for the class and in the current year, the National entry was down to nine boats, There is no doubt a consensus would suggest the boats are now too fast. How much significance can be attached to the fact that the addition ofradio control events has overweighted the figures is difficult to estimate in that the 10R class, always third in popularity, has suffered most. Finally some may consider it not overly sensible to spend time and money pbuilding a boat that has a twentyfive percent chance of being damaged as soon as the wind pipes up a bite With hindsight it seems obvious where the problem lies, The intention of the rule change was to rationalize the “rate of” and to avoid “excessive” development of unmeasured sail areas via the mainsail roach, Simple arithmetic shows that at sixtyfive inches IWL, under the old rule the measured sail area would be 1000 square inches, under the new rule,.1154 square inches, Compare then, the old and the new; “Sirocco” (35: 54: 1380:), unmeasured actual area; “Synergy” (22: 65: 1150:), actual area. Proceeding with our arithmetic, we find that “Sirocco” had thirtynine square inches per pound of weight and twentyfive square inches per inch of length. The new boat; “Synergy”, fiftytwo square inches per pound of weight and eighteen square inches per inch of water line. The “on wind” performance is not eritical but 10R there is cont’d little doubt that the substantial improvement in the power/weight ratio is responsible for the daunting planing spneds of the latest boats. Whether this is a good or bad feature tends to depend on age, cash, enthusiasm and the devoted assistance of a young and energetic mate! The radio class as yet without spinnakers does not suffer from the same problem; under firm @ntrol on the water, suitable prayer. they are not launched with crossed fingers and a Or shouldn’t be! It can be assumed that if in due course, flying, mostly arrangements will exist to get spinnakers are carried, them down at will. that having got them Even so, the thought of a radio or mechanical failure on one boat in a flcet of six does promot the thought that suitable insurance cover should be advisable. Although opinion – Hollom, Kay, Lewis’s (“Pulsar”) and Stollery – indicates the suitability of a design giving disnlacement of about twenty pounds, LWL of about sixty inches and sail area of about 1250 square inches, others – Nylet, Fuller and Dicks (recently announced “Hellbat”) — have turned about and go down to below fiftyfive inches and twenty pounds with sail areas of above 1350 square inches. Tim Fuller’s “Nookie Bear” has been around for four years and carries over 1500 square inches on a fortyeight inch LwWL. John Lewis has also entributed to the light weather group with anew boat, two examples ° of which (17.53 546 1350:) have recently been comnleted by Ken Jones at Birlenhead. Stollery’s “Roundabout” may also become available shortly if his plens mature. Discounting, as always, the abilities of the skipper, it is logical two groups ofboats are suitable designed on a As a design class, 10R has so much potential for development, the to assime that the “horse for course” basis. yet unexplored, it is ideal for the model yachtsmen who enjoys designing and building “one-offs”, that There is little point in designing and building a racing yacht if it cannot be raced and the significait decline in the number of events for the class and the excessive downwind sneed could result in a situation similar to the decline which faced the Six Metre class in years paste Enough experience has been accumulated in the ten years during which the 7500 rule has operated to suggest another look at the rating formula. If it is agreed that the excessivé offwind speed is detrimental and that this characteristic by the existing rule, has not been adequately condition then the spinnaker area which promotes the excessive offwind speed needs new consideration. The formation of a Ten Rater Association shows that interest and enthusiasm still exist. Long term benefit could come from events held by them in which the spinnaker area would be related to displacement rather than sail area or water line length; it should not be too difficult to devise. A benefit also to those interested bodies now develoning middle-aged spread and reducing leg power. WHIRLWIND NEW Mk, III SAIL WINCH THE SAIL WINCH for RM and R1OR Yachts. : Wy Me. IIT Suits most R/C equipment, fully proportional, high power, light weight. The ideal answer to independent Jib and Main Control. Prices £42.00 (inc. P&P and V.A.T.). S.A.E. for details. D.H.Andrews, 49 Aberdale Rd., Leicester. Tel. 883309 4 Try your hand at this when waiting your turn to sail. First correct solution received will be given a free subscription. Clues set by Graham Bantock, who says he knows the answers. Answers will be published next issue. across 1, One design helming will be 6. Spinnaker material 9. Common material (abbr.) 10. You are part of it perhaps 11. Width of rudder, Compete Match race entry –— headed; International A class winner 1978, first part sounds musical 14. This plus 7 down often called (2) 16. 17. Too late to prepare for race Downwind side 18. Refrigerated cargo vessel 3) 3) 20. Athwartships 23. Finishes last 24. In charge 25¢ Depth? 26. Breaks 28. Frome, Bude, Run (anag) Bill’s numeral 30. Australian M.Y.A. is down there 31. 32. 34. 36. Makes lightweight winch Fluid Stops sail twisting Many start with one (abbr) Nautical Cat’s chances? Useful at a buoy Beats 800 on a Marblehead 3 May be found at head of , L 8) Downwind 6 sail Component of early R/C 5) On Lionheart’s quarters 3 725) 2 Good leeward position 42. Two inches on a Marblehead 44. Required to rate A, 6M & 510) Increase this to improve speed 48. May assist with 34 across (7) (5) (8,4) (9) (4) Bee Just win 39. 47. (4) down. 4 May help with arithmetic (4) Aspect ratio, short for Usually the largest of 40 (5) Base of mast 45- (3) Raced for at Easter 6,6) 37. 10R fishy! (4) (3) 336 346 A smooth one is essential Propels power boats, noisy Prevents leeway Keep mast upright —R,. Once described tall suit Centre of area or centre of ? Help! ) These provide motive power (12 ) } At. Supports boat 436 First switch — 46. Seahorse for example i 5) OLIVER J. LEE ONE METRE FIVE POINT ONE DES IG N 1.50m -32m Length 0.A. Beam Draft 46m Mast Height Displacement Keel Weight 2.40m. 10.90kg. 7.15ke6 The A finely engineered racing machine. ultimate in R/C yacht racing. And above all it’s a ONE DESIGN with strict rules, and a strong and lively OWNERS’ ASSOCIATION. It’s BIG (Nearly ten feet tall, if you haven’t gone metric). It’s FAST AND POWERFUL (carries 1450 sqeins. of sail in winds up to Force 4). Mrs. J.V. Snelling, 362, Plumberow Ave, – Association Secretary Hockley, Essex. Large discounts for clubs seeking to establish a racing fleet of ONE POINT FIVES. fi = | / K2t88. | \ \ / Le // \ } || q| Lb + | | || | RM TRAPPER \ of | \ \ Winner of 1979 NATIONAL R.I!. CHAMPIONSHIP A Marblehead Class Radio Controlled racing yacht of outstanding performance and of the \ \ highest standard of construction and finish. : The kit includes a one—piece hull/deck moulding complete with keel trunk and rudder tube weighing less than 2} 1b. Fin keel end rudder cut to profile. “GROCVY’ mast, booms, fittings and suit of BANTOCK “At rig sails. Fully detailed drawings and building instructions. Hull moulded in coloured gel requiring no painting. Radio and lead keel not included in kit. Send S.A.E. for complete price list etc.,. 29 Chapel Rd., Burnham on Crouch, Essex, CMO 8JB Tel. Maldon (0621) 782305 –> Portrait of Oliver Lee The opportunity arose over the Christmas holiday of talking to a man who has made a considerable impression on the radio-yachting scene in the last few years. In the first of an occasional series of articles we look in more detail at the development of his yachting and model-making interests. the man Born in Lincolnshire, educated at Kings Grammar School, Grantham, he claims to have been more interested in model aircraft and sailing boats than the school curriculum. During three years army service in the Middle Hast he joined the Services Yacht Club in Egypt and persuaded German P.O.W.’s to build a ten square metre yacht in exchange for six months! cigarette ration. Returning home, he first served five years apprenticeship with Burnham boatbuilders, Tucker Brown & Co: and followed that with ten years at Alan Buchanan Limited and became a director of this yacht design firm. He became an exvert dinghy helm, mainly in Hornets and tied for the 1954 World Championship. Not content with this he also took up gliding and gained the duration part of his “Silver C” certificate using a Slingsby Swallow constructed in his garage over a two year period. The glider was sold in 1964 to provide capital to start his own business surveying yachts and building racing craft. big boats Without doubt the best known of his designs is the “Squib” nineteen feet racing keel boat which first entered production in 1968 and has sold in emsiderable numbers ever since. Perhaps less well-known are the Hunter Boats Limited designs; “Hunter cabin top), “Hunter Europa” (more accomodation, self draining cockpit) (a bigger yacht altogether). These are all Oliver Lee designed and of newer “Tracer” variable draft keel boat together with the “Sandhopper” New designs are to be 19 ( a “Squib”with and the “Hunter 701″ course there is the (a bilge-keel Squib”). seen on the drawing board and in one case a prototype is nearing completion so Oliver continues to maintain an active interest in this aspect of his career. little boats With his early interest in models in mind, it is not difficult to see that the advent of miniature radio equipment and the formation of the Bad&ldon M.Y.C. would encourage an immediate response from our man{ So indeed it was, and the purchase of a Nylet “Moonraker” started things off. As you might expect this soon set off ideas of a persnal design md the result was the first “SQUIBLET” RM, The displacement of this boat was around twentytwo pounds (the hull itself weighed four and a quarter pounds), Skyleader radio with a monoperm-motor winch was fitted and the developments started from this point. “SQUIBLET” Ten Rater was a stretched version which has since developed into the 1*5Metre. “TRAPPER” Mk.I was of about sixteen/seventeen pounds displacement and set the basic layout of the type, which has continued in production ever since. “TRAPPER” Mk.II was lighter, the fin shape altered and the mast moved back. “TRAPPER” Mk.III has the distinctive chine at the stern, to improve directional stability off-wind and the mast moved further back still. Experiments with a variety of fin/rudder shapes including a bustle have been tried and discarded in a constant effort to improve the breed and the 1981 production model “TRAPPPER” Mk.IV revresents the very best efforts of Oliver lee to provide his customers with a first class competitive boat. The full 1981 range includes:Trapver Mk, IV, Squiblet 10Rater, 1°5M One-design. Other model yachts have been seen in Oliver’s hands during the last few years and in particular a very attractive RA of fortytwo pounds displacement, 1414 square inches sail area, which he is not too keen on recommending because the off-wind performance in Force 3 and above is somewhat twitchy! Orders for”Trappers” continue to occupy the majority of production time and in addition, all the bits and pieces are now available separately. place in the beautifully converted cottage When our conversation, which took in which he lives, ended, he set off towards his workshop with a very purposeful look in his eye so we may expect further developments in due course! The current project is a thirtysix inch long boat, close resembling an off-shore day racer with the underwater shape modified to provide a good performance. ‘The prototype is taking Shape at the moment and the profile drawing gives a very clear impression of its overall appearance. Designed to meet the growing demand for a convenient-sized yacht that looks “scale” and yet gives good handling ina breeze, we shall report further on this new venture in due course. ry HARRIER LOA 36″ BEAM 103″ DRAUGHT oan DISPLACLILINT 11 lbs, JONES FITTINGS Top quality fittings for vane and radio for all recognised M.Y.A. classes. tacking vane gears also available. Self Your own special fitting made to order. 35 years experience in mamfacturing of yacht fittings. proven by most National and International champions, home All fittings have been and abroad. S.A.E. for comprehensive list and prices. 35 The Paddocks WITHAM Essex. Tel. WIT. 516248 yoojueg weyesy E.L.JONES, 8 Marline Avenue, Bromborough, Merseyside. ASHTON MODELS 201, OLD ST. IT’S HERE? ASHTON-UNDER-LYNE, LANCASHIRE. OL6 7SR 061-330-1137 THE JACKSON MK.4 SAIL WINCH IT’S FAST……..-sheets R.M.s from running to close hauled in under 2 secs! IT’S LIGHT……..Winch & amplifier together now under 100g. (34 oz.) IT’S POWERFUL….-Handles R.M.s & R1IORs with ease. RA class successfully. It’s even being used in IT’S RELIABLE…..Water resistant mechanics can be mounted. up to 9″ away from amplifier unit so electronics stay dry in radio box. IT*S ECONOMICAL…Longer battery life! New circuitry combines absolute maximum efficiency, with crisp, positive proportional control. IT’S VERSATILE…-Plug—in leads, to receiver, winch mechanics & battery allow instant removal of winch or amplifier, without resort to a soldering iron! The wiring stays where it is. IT SPLIT’S…….eWinch & Amplifier can be purchased separately, either to reduce the cost of a secon installation or to simplify the transfer of equipment between boats. IT’S AVAILABLE….NOW..From stock. Winch, amplifier and leads complete £45. Mechanics only….£23. Amplifier only….£24.50. SEND S.A.E. for full info. & get our illustrated cat. of yachting goodies’ RADIO CONTROL SPECIALISTS…MAIL ORDER NO PROBLEM… BARCLAY-CARD-VISA. VICTORY SYNDICATE ENLISTS HELP OF LEADING MODEL YACHTSIial. ACOR Ni Six leading British designers of model yachts have each agreed to design an America’s Cup Twelve Metre. Challengers, Together with similar sized one-tenth scale models of the Cup “Lionheart” and “Australia”, these will be carefully built by one man, using common methods. Extensive sailing trials in various varts of England will then follow, using the and “Australia” models as yardsticks, “Lionheart” Alternative reduced rigs will be used when the wind is too fresh for the full size equivalent to have relevance. (A five knot wind at onetenth scale is equivalent to twelve knots at full size). If certain designs or features prove emphatically successful, the next stage would be to try them at increased scale. Finally, Ed Dubois, Design Coordinator for the Victory Syndicate’s 1983 America’s Cup Challenge, will be free to adopt ideas or a complete design for a second new Twelve Metre yacht which the syndicate plans to build in 1982, the model trials are completed. Their first yacht will be built before Dubois is hoping Project Acorn will suggest new approaches that would be difficult to evaluate in the towing tank and would be prohibitively expensive and risky to try full size. The six volunteer designers are:DICK PRI“ST, co-author of a standard work on model racing yachts, designer of many past Championship winners and an experienced Dragon class helmsman, DAVE HOLLOM, winner of the National Radio Marblehead Championship, Champions Cup, GRAHAM BANTOCK, 1980, with models of his own design. graduate of Southampton University’s Naval Architecture Department, winnner of the National Six Metre Championships, CHRIS DICKS, 1977 and the RM Civil Engineer, with his own designs, 1979 and 1980, with his own designs. very experienced skipper and successful designer, no less than fourteen National Chmpionships having won, in the Marblehead, Ten Rater and A Classes. ROGER STOLLERY, designer, Architect and keen student of yacht design, brilliant skipper and clever having produced a total of forty designs, including several outstanding successes in three classes during the last decade, PHIL MORRISON who, racers, has besides being a leading designer of racing dinghies and small offshore extensive model experience, The builder is Guy Winder, of Shipley, West Yorkshire, well known for his superbly built “Merlin” dinghies. He will plank the models over wood frames. Four channel radio will be standard. Sheeting, steering and trim tab controls will be standard too. Sails and sparswill come from single sources. Project Acorn, so called because “great oaks from little acorns grow” is intended to complement and not compete with the Victory Syndicate’s main stream tanking and research programme. The Project organisers are looking for suitable venues for staging the trials, expanses of water, such as reservoirs, are preferred to ensure waves, Large even in light airs, If any sdling club would be prevared to offer their facilities and provide a follow-up boat during the coming season, would they please contact Norman Hatfield, Hon. Secretary, Project Acorn, 26, Shanklin Drive, Westcliff-on-Sea, Essex SSO 9XU. ‘Telephone: 0702 44389, from whom further information may be obtained. 10 sf — 12 12 2» Following on the news of Project Acorn and the new challenges for the America’s Cup being mounted by Britain and other countries, we thought it might be interesting to examine the 12 metre class rule. Little is ever mentioned about the rule to which these yachts are designed and the problems which face the designer. The rule itself, whilst tying the designer down to produce what might be called a normal type yacht allows much subtle variation in lull shape. RATING (12m) =L + 24 + VS It is based on the formula:- – F 2957 where L = length, d = Girth difference, S = Sail area, F = Freeboard. The factor of 2.37 is incorporated simply to ensure that yachts rating 12metres are of a particular size. It is important to note that the length L is neither the LWL nor LOA but the length measured at a height of 18cm. above the LWL plus additional measurements depending on the shape of the bow and girth sections (described later), thus:- L In + (FGD x 14)+(AGD x 4) This measurement affects the angle at which the profile of the hull emerges above water. It is not possible.to have long, low overhangs to increase the effective LWL when sailing heeled ‘as no hollows are allowed in the surface of the hull between LWL and the sheer line. As the minimum displacement of any 12 metre yacht is dictated by its LWL and increases rapidly as LWL increases, a designer will usually seek to achieve the shortest possible LIWL for a given L measurement if he wants a good light weather boat. Conversely if the design is to excel in stronger winds a longer LWL, greater displacement and hence stability, will be chosen, To discourage undesirable overhang shapes the rule adds to the In measurement girth difference measurements taken at the bow and stern endings of In. ‘The positions at which they are taken are illustrated in the sketch, At the bow ending the distance round the skin of the hull, PQR, is measured to points five percent of the rating above I2 (P & R). From this distance is subtracted twice the vertical height from In to these points ( 1.20 metres) and the result, FGD (forward girth difference), multiplied by 1}, is incorporated in the L measurement. At the stern ending of Ia a similar measurement is taken, MNO, from which twice the vertical height is subtracted, The result, AGD (after girth difference) is multiplied by $ and incorporated in the L measurement. The effect of both these girth difference measurements is to make U sections expensive in terms of sail area and to encourage V sections. narrow bow and stern overhangs in the rule are However, in order to discourage extremely (small girth differences) minimum values which may be used specified, Having controlled the ends of the hull, the rule makers further limit the designer’s scope by influencing the tyne of midship cross-section, in the formula. and this is done by the 2d figure This is another girth difference measurement and is taken in a transverse plane at 0°55 LWL from the fore end and is the difference between the girth around the skin of the hull and what is called the chain girth, point 12¢5 percent of the rating below LWL, taken from the covering board down to a The chain girth is the length that would be produced if a piece of string were stretched between the two voints of measurement rather than following the surface of the lmll. The resulting girth difference is doubled and added in effect to L. It should be obvious that a hull of scow type will suffer a severe penalty due to this restriction whereas a deep V tyne hull will have practically no venalty. if a rule Now, encourages a V type hull, the designer, in order to get the best possible speed will make it as narrow as possible, beam of 3600mm (11.8 ft.) so once again the rule prevents excesses by imposing a minimun 14 Other restrictions affecting the hull design directly are:- 3} A maximum draught of sixteen percent of LWL. + 0*5m b) The maximum value of F used in the formula is c) ad) but it will not increase sail area, 1*21m. Yachts may have more freeboard on the other hand those with less, The tumblehome must not exceed two percent of the extreme beam. 3 The minimum displacement shall not be less than (0+*2 LWL + 0°15)? lose area, cubic metres. The penalties incurred by exceeding the requirement of these additional rules Sometimes accepted, are although infrequently. oO M&O waterline So that no unfair advantage can be taken by the misuse of equipment for racing purposes various restrictions are placed, less than 45kg. weight. liquid refreshments). e.g. the quantity of water in tanks and batteries must be Consumable stores whilst racing may not exceed 68kg. Various rules govern the area of deck openings and volume of cocknits. (including These have undergone quite substantial alterations in recent years and have been responsible for bringing crew members back onto deck = at one time the crew spent most of their time below decks. The rating rules require that the scantlings and materials of the yachts are governed by construction rules issued by Lloyds Register of Shipping. each yacht would have a long and safe life. With the present rate of development in 12 metre design and their use virtually only for one event, a necessary req:irement. Originally this was to ensure long life is of course, no longer However the tight construction rules do mean that the weight of each hull less lead is virtually the same in all cases and prevents the necessity for expensive and tedious construction techniques. ‘The cost of hull construction is usually only a modest pronortion of a challengers’ campaign budget – most going on design, development, sails and tuning. Sail plans on these boats are almost identical with only small variation in measured area. On the other hand the sails are the key factor and the choice of materials and cut plays a erucial role in the success of any particular yacht. Wo amount of clever hull design can offset an inferior sail or the wrong choice to suit conditions on the day. The mast of a 12m will stand nearly 27m. high and they are very carefully designed. The rules specify minimum diameters, minimum weight and the position of the centre of gravity, but the actual method of keeping it in »lace is not fixed. The sail area is measured im much the same way as the model A class rules. It is interesting to note that in order to maintain the present near status quo in 12 metre yachts’ performance, (a 2% winning margin is considered large) the IRYU Committee who maintain the rating rules have moved swiftly to introduce a half and three-quarter height measurement. This will effectively stop the gain in unmeasured free area by the use of mechanically bent mast a la Lionheart and Australia. yachts may continue to be used on them as they are excluded from the new rule by a “erandfather clause”, the The masts and sails on these two in much the same way as the Clockwork Orange A boat is exempt from revised deck camber rules which stonped further boats being built this way. “WARNING” In prevaring this article the Editor consulted a number of sources including books on 12 metres, articles in past yachting magazines and the 1976 12m RUL&S, Before you spend £200,000 on a new boat nlease consult a qualified designer! 12 further afield NORWAY. A national championship for RM class was held on the 5th. October, at Tunevannet, Sarpsborg. 0.0.D. was Jan Dejmo from Sweden who used the fleet system to sort out the thirteen entries. Winner was Torvald Kem sailing a “Challenger”, followed by two “Trappers” and a variety of “Seahorses” and “Challengers”. In seventh place, Gunnar Karlsen sailed one of the first vane HM boats in Norway, now anverted to radio. — My command of Norwegian is limited to school-boy skiing holidays, so I have yet to decode the newspaper report kindly sent by our correspondent! Thanks Torvaldé SWEDEN. Received from Jan Dejmo a copy of their Bulletin which has some fine photos of a French RM with every concievable extra omntrol on it. Listed in their 1981 calendar are several RM events in Stockholm. Also the address of Bengt Bellander, who is selling one tenth scale mouldings of the Swedish 12m “SVERIGE”, which we understand, the Swedes are now sailing as a class, Bearing in mind that Peter Norlin is using R/C to develop new 12m designs, these appear to be the current trend. GERITANY. A new club in Iudwigshafen area held an open RM regatta in October and we have received some excellent photos and a report. Four Swiss, two French and twentyeight Germans competed on a fine open gravel pit. A win for Helmut Iupart from Switzerland, sailing a design we don’t recognise and another Swiss, Werner Uttinger, in fourth place. Report from Walter Piel. CANADA. Recently talked to Bob Sterne from Vancouver area, who produces a range of GRP shells including two 36/600, four RM, including the M.A.P. designs ‘Sailplane” and “Kokanee” and some home-grown designs. Also listed in his catalogue is a range of carbon-fibre mast tubes of lengths between 50 — 100 tinches, tavering from 3″ butt to 3/8″ top 0.D. At five ounces, a weight saving of three ounces compared to dural of tynical size is available. He also produces an EC12M hmll, but before you order one, check that it will be acceptable to the local National Authority, because he has deepened the draught, (within the rules in his opinion) and it wos not allowed to sail at the Mini-Americas Cup. Full address; Bobs Boatyard, 6389, Beresford Street, Burnaby, British Columbia, Canada. ITALY. The October edition of “NAVI & MODELLI Di NAVI” contained a detailed article and plan for a working model “Flying Dutchman” dinghy, complete with trapeze wires, spinnaker, etc., The accompanying photos show it sailing in very light winds with only a centre plate as ballast. ‘The magazine is similar in size to “Model Boats” but more interested in galleons and historical models, if this edition is typical. If any of our readers in the South East of England are fluent readers of a help== language, I would be very hapny to hear from them so that we can extract the maximum information from the magazines I receive. [| eg. Ti LUFF WIZE TERMINATES INSIDE LUFF TAPE = OUTHAUL ADTUSTMENT, BEND PRom é) y, IS GAUGE SPAIMESS WIRE. Rveser ‘O’ RING RUBBER BULKHEAD GRowmETS, NOHT FIT ( t ON Boom 1.6. S/iib” TDONA 3/e” Boom, — ATTACH HOOKS WITH Cord, | Z ALLL FITTINGS ON BOOM SLIDE TO SvuiT VARIOUS JIB FooT LEWeTHS. LOCATES, IN AW ONE OF A Pow OF [ BB Any volunteers @ asic RIC Starboard /\ ede – side SIN Mainsail, t f a (p* On_ Mainsail | nt board sidi BASIC R/C RULES LEAFLET. Reprints of the centrespread from issue Noe 4 are available separately. Minimium order of 15 copies only – Price 10p. per leaflet -— post free. Single copies, send a Stamned envelope plus a 14n. Orders starboard tack. ior i Running, is windward. S q