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NOVEMBER 1959 £50 BOAT PRIZES SSS 4 ET MODEL MAKER) . RR Ate a aa Impala i A new 10-rater designed angle of the water-lines at bow and stern, which is a disadvantage in light weather both upwind and down. To show just how great this effect can be I recall reading a tank test | report on the performance of two models of similar length and displacement but with the one having finer ends than the other. It was found that in the range between zero and the speed at which both had the same resistance, there was a point at which the fine ended version required only two-thirds the power of for top-class all-round performance BY S. WITTY Re eee ROM time to time someone asks why it is that a good “M” design can often hold and sometimes out-beat a good ten-rater in moderate or light conditions. It may be considered that the current popularity of the “M” class has resulted in these craft attaining a higher standard of development than the latter. Personally I do not think this is so but nevertheless there must be some major reason for this. A comparison of the two types leaves us in no doubt which should be the faster, the respective sail areas being approx. 1,110 sq. in. to 840 sq. in. (by ten-rater measurement) with the wetted hull areas in about the same proportion. It would seem then that the type of hull form encouraged by the “M” class rules is advantageous in certain respects. These rules state that the maximum overall length of the hull must not exceed 50.25 inches and as length on the L.W.L. is an important speed factor it follows that this should be as long as the particular design concept will allow. Due to this the length of overhang is seldom more than two or three inches resulting in much finer sections at bow and stern. This is true even of a design with an abbreviated stern when compared with a normal ten-rater which, according to the rules, can have virtually unlimited overhangs and quarter beam length. Because of this it is usual to try to squeeze as much of this free length out of a given rating as possible, with the result that the fullness of the sections at bow and stern is much more pronounced. Added to this is the fact that out of balance considerations most designers attempt to forge some sort of similarity between bow, stern and mid sections, and as a ten-rater mid-section is usually flat floored in order to obtain good planing qualities it follows that the sections at the water-line ends will also be somewhat flat in character. This results generally in a coarse 488 the other in order to reach the same speed. Some weight is given this by watching the action of fine ended designs such as H. E. Andrews’ Allegro which has a very creditable performance in light weather although having a sail area of only 1,000 sq.in. As a rule though it is the older boat with a W.L.L. of around 48 in., and carrying more canvas than contemporary designs, which collect the most points in these conditions, although this is due to the more advantageous sail to wetted area considerations, rather than to the hull form. As stated, performance in these conditions is partly hampered by balance considerations and I think it would be fair to say that there is a certain stage in the draughting of any design where the balance of the yacht cannot be further improved without materially affecting the speed. In the design shown these considerations have been taken into account and as a result she will be rather faster in light airs than the average ten-rater without any reduction of the heavy weather capabilities. To get the most out of the limited amount of sail area it is essential that the hull should provide a really steady sail platform and give a smooth heeling action, free from any hard spots, otherwise the airflow over the sail may be temporarily disrupted, killing both the power and the speed. Probably the real test of the balance occurs in really squally weather, where all the different combinations of wind velocity, speed of hull, angle of heel, etc., are rattled through in rapid succession. Naturally in these conditions the course of the yacht will not be exactly straight as she must head up into the wind when hard pressed in order to keep sailing, but the impetus given by a gust should only cause her to alter her angle of attack sufficiently to ease her and not to swing in an are so that she is left with gear slatting in the hull. as In order to match the power of the heavyweight designs the fin has been given a draught of 14in. and due to improved design technique this does not look at all out of NOVEMBER, IMPALA ca emer’ (86 MODEL MAKER PLANS SERVICE 7] DETAR ee—>S 7 = fl : – = > : — 1959 Ls t ——————-7 et eas SS ee| — = > X 1S*X 35° 4TH | 34 SX OSX 3″ FULL-SIZE COPIES OF THE ABOVE DRAWING, WHICH SHOWS BODY PLAN AND FIN LINES FULL-SIZE AND SHEER AND WATERLINE PLANS HALF-SIZE, ARE AVAILABLE PRICE 9/- INCLUDING pita FROM MODEL MAKER PLANS SERVICE, 38 CLARENDON ROAD, f proportion. WATFORD, It must be remembered that a draught of around 11 in. has-been more or less standard in this class almost since its inception. Only in the last two or three years has there been any significant increase in this respect. and then hardly enough to counteract the power of the high sail plans of today. In addition to the increased power, a deep fin also HERTS. suit individual tastes without upsetting the design concept as a whole. My own view is that except where the overhang is very short the choice of stern is more a question of aesthetics than performance, and the true transom stern as drawn easily and if anything a can be built little lighter. more In the same manner the foot of the foresail may be gives a greater resistance to sudden changes in the angle of heel due to the damping effect, and this helps to preserve a more steady sail platform. Impala differs a little from previous designs in that there is no snubbing at the bow sections, and it may be advantagous to round these off slightly when the hull is reaching the final stages. The stern can also be modified to extended a couple of inches should the builder prefer to use the more conventional free jib instead of the kick-strap version as shown on the drawing. WARSHIP [DETAIL (continued from page 491) of a model if shown folded and stowed inboard, and a whaler is so elegant a boat that it makes an interesting study as a model by itself. It would be possible to make a large model that would sail in light winds by fixing a detachable shaped piece of a model of a Tribal class destroyer carrying them would be nearly 4ft. long. In the Admiralty Manual of Seamanship, Vol. I, p.184 (which is available to the public through H.M. Stationery Office), there is a very fine shaded perspective drawing sectioned along the middle line of a whaler, with a similar one of a 32 ft. cutter below it. A reference to this and to the information in Vol. II would clear up doubtful points not covered by this article which would have been of much more value as a historical record had the Admiralty preserved the specification book and made it available to the author, the more so as the traditional wood-built whalers are now being replaced in the Service by a heavier version, lead to the lower edge of the centre board. It is difficult in a small drawing to show the leads of the sheets and halyards but most of the latter are made fast to belaying pins passing vertically through the mast thwart and the one next to it, the sheets being held by members of the crew. The original of this drawing is }-in.=1 ft. scale which is very large for a model of a warship requiring whalers. At 4 in.=1 ft. the model would be 33 in. long overall, but even so . 489 5 Ee ee Oe SSS On the whole Jmpala is designed not merely to achieve an improvement in any particular respect but rather to increase the entire performance over a wide range of weather conditions. with power drive, made from glass fibre. HT MODEL MAKER THE FIRST NATIONAL RIC YACHT CHAMPIONSHIP Extracts from first-ever ‘‘official’’ H. E. Andrews’ event. Left is report the on the handsome trophy presented by Model Maker to mark the occasion mark. This manoeuvre was often spoiled, however, by the more wily skippers laying off from the catwalk on the port tack and then, after tacking to starboard just to loo’ard of the North buoy, forcing their opponent round by calling “‘Starboard’’ and giving them a dose of dirty wind as they passed. WITH the adoption of R/C sailing rules’ the M.Y.A. Council decided at their September, 1958 meeting, that the time had come for the first National R/C Championship; the meeting was held at Poole on August 29/20, the Poole club having something of a radio and full-size racing background. Since this meeting was to a large extent feeling hardly the be way, normal followed; procedure preliminary could literature was circulated to all clubs of the M.Y.A. and I.R.C.M.S., and entry forms were sent to all persons thought likely to enter. Ex. ““A’’ class boats were to be used, since these at present form the majority of yachts converted to radio. Since these yachts are not actually recognised by the M.Y.A. it was decided that a trophy would not be provided, but the race would qualify for the normal grant from funds and that honour certificates would be awarded. Unfortunately, heavy commitments in Poole Yachting Week caused the appointed 0.0.D. and two members of the special committee to withdraw at a late stage and the club therefore appointed H. E. Andrews as O.0.D. It was decided that each yacht would sail two rounds of the course against each other yacht on the normal tournament-system, the winner to take five points and the loser two. Two rounds would be sailed, three if time permitted. When the six entrants reported on the Saturday, one was forced to scratch due to radio difficulties, but the yacht Vanessa had arrived and was allowed to substitute for the scratched boat. The first heat com- menced at Il a.m. and despite crystal control, it was found that one boat, No Name, had interference trouble although the other five could sail together. It was decided that each boat of the pair would make a timed circuit of the course where this difficulty arose. The light North-East wind gave a running start across the line, but this caused no difficulties, contrary to expectation, most pairs making a good start with very few beating the gun and having to be recalled. Most skippers in rounding the marks preferred to make sure of clearing by taking them fairly wide, but many times boats astern managed to secure an “overlap by luffing sharply round and passing inside their opponents, thus securing the lead on the next leg. With the wind from the NorthEast, the windward leg of the course was from the catwalk buoy to the North buoy and many skippers found it to their advantage to lay along the catwalk on the starboard tack to remain in the stronger wind and, when well to windward of the North buoy, to lay off full and bye on the port tack to clear that There were no untoward incidents in the first heat, but in the second there occurred the only protest of the event. Senorita and Vanessa both sailed their starting manoeuvres without trouble and Senorita had the best of the start, running down the South mark, rounding and reaching over to the catwalk buoy. When there, she touched the mark and retired, leaving Vanessa to sail round to get the winner’s points. Unfortunately, after crossing the line her helm jammed and she commenced circling near the clubhouse, her mate helped her to the shore with a pole and this was the subject of Senorita’s protest as she declared that Vanessa had contra- vened Rule 21 (2) “Under control at the Start’’ and Rule 23, “Making fast or Anchoring’’. Vanessa incidentally, had cleared her fault and had completed her two rounds of the course, being awarded five points. At the end of the heat the Sailing Committee with the O.O.D. in the Chair sat to hear the protest. Senorita and Vanessa made their points and then withdrew. After discussion the Sailing Committee agreed: 1. That Vanessa was under control at the 2-minute gun, 2. That a model yacht hitting the bank is equivalent to a full-size running aground within the terms of Rule 33. 3. That Vanessa was helped to the shore and that therefore extraneous help was given to propel her. The Committee unanimously ruled that on the grounds of (3) above, the protest should be upheld as Rule 24 had been broken. Vanessa was thus awarded only two points for her heat, the same as her opponent. Thus the first bit of case law was made for R/C model yachting. During the remainder of the day’s sailing Morven II was out of action due to her owner being engaged with the ‘‘X’’ Class in a race in the harbour, it being agreed by the O.0.D. and her competitors that the remainder of her heats should be sailed on Sunday. Also the other boats with the exception of Kit and Sundial were plagued by radio trouble and caused considerable delays. However, the event continued and sailing was only terminated at 5.30 p.m. by all hands being unsighted at the catwalk buoy because of sunglare. At this point Sundial was in the lead with Kit close behind. On Sunday the first pair were away at 10.10 hours, the wind and weather being as before. Morven’s arrears 510 —— were run off without trouble and three heats were finished before lunch. All the yachts behaved well and it was clear that skippers had benefited from Saturday’s practice as tactics were much improved and some exciting situations developed. Vanessa was, unfortunately, again in trouble in the last heat, when her rudder again jammed and she ran ashore on the catwalk. The O.0.D. commentating on the P.A. system had just compared her plight to that of a full size yacht run ashore with her mate jumping into shove her off when her mate fell off the catwalk on top of her, breaking her mast at the hounds. Her radio gear was also put out of adjustment by this mishap. During lunch her mast was fished, her gear adjusted and she came to the line after the interval seemingly no worse for her mishap. After lunch the wind fell very light indeed and it was fortunate that only two heats remained. Notwithstanding the fluky conditions racing was both skilful and close and the crowd of some three hundred spectators were silent at the spectacle and the running commentary given by the O.O.D. over the P.A. system, applauding enthusiastically each piece of clever tactics and each result. On completion of the second round it was seen that first and second places were clear, but the two local boats, Morven I] and Sundial had tied for third place. A sail-off by these two boats, twice round the course, resulted in a win for Sundial as her opponent fouled the catwalk buoy and withdrew. Ist. 2nd. 3rd. 4th. Sth. 6th. RESULTS Vanessa T. G. Carrington-Wood London Gp. I.R.C.M.S. 41 pts. Senorita J. Gascoigne -M. 6m. O.A. Sundial J. G. Hogg Poole M.Y.C. Morven II Lt.-Col. Bowden Poole M.Y.C. Kit A. Tamplin Gosport M.T.C. No Name J. Merrick B’ham Gp. I.R.C.M.S. 38 pts. 35 pts. 35 pts. 32 pts. 26 pts. CONCLUSIONS 1. For size of entry a R/C event demands more organisation than an ordinary race. 2. The tournament system of sailing gives all competitors a full session of sailing. It provides a continuous spectacle for spectators. With larger entries heats are not necessarily limited to two boats as with current equipment 3, 4 or 5 boats can be sailed in each. A system of scoring on the Olympic pattern would, however, be necessary in these cases, i.e., in a fourboat heat three points for winner, two for 2nd and one for 3rd. 3. The system of scoring for this race was not effective. The two points for the loser was given on the assumption that all boats would complete the course. In fact the Rules said that disqualified and withdrawn boats should sail back to the start. Thus points were given when they were not deserved. 4. A P.A. system is essential for timing starts and instructing competitors. A running commentary (without guiding competitors in the Rules as situations arise) is helpful to all hands and adds to spectators’ enjoyment and understanding of what is taking place. NOVEMBER, The Future of Model Yachting Fig. 1.—Spinnaker measuring. With spinnaker folded equally, I to be not more than Jib Hoist less 4 in. (subject to maximum). J. A to A round J. S. Drury concludes with practical for remedial measures OW the taking of action to correct the develop- ment of an unhealthy situation is not really a case for the cry of “ichabod”, though this will doubtless be raised here and there. Let us consider other sports for a moment. In ’47-8 the Table Tennis authorities utterly banned the knuckle and finger spin services, though these were really something to watch, and match-winners for the adepts. Rather a howl went up here and there, but the sport has never looked back since. Last year the Yacht spinnaker, from edge to edge at height B. Now step? Racing you object to the amendment of rules as a bar against progress you are, so to speak, disputing with yourself. (a) (b) / something ! |; |, Well, one that would‘*” save anything else, all amendment to rating rule, etc., would be “ban spinnakers entirely”. Whoops! Hold on to your hatches, it’s not so fantastic as all that; count ten slowly and then consider with me that it is already done with radio control models, and with some full-size smaller classes, too. We made but little use of them pre-vane, and had just as much fun, and we should not have the bother of rigging and unrigging them, tangling and untangling lines, stowing wet ones about our persons, and awkward booms, nor delaying the “call” and hadn’t been stopped we could easily have rated a full size 12 Metre as an A, or the “Cutty Sark”! So that if you build to a rating rule at all you accept the idea of restriction upon design and speed, and if but include me out. Now when we accept the conception of rating and racing rules as something intended to produce the closest and most even racing we must add a sailing rule which will prevent a skipper from changing up for the run and down for the beat, in hard weather, as a matter of policy, or anything we try to do with sail areas will obviously be set at nought. The following is a draft which should meet the case. regarding equivalent to the above rule as a fact, what is the next Associations introduced completely new sailing/racing rules, scrapping literally volumes of precedent and case law in the interests of greater safety and the prevention of possible abuses. So we are in good company in tackling our problems, which are: without outmoding the existing fleet, introduce a measure of control over increasing size of each class, sharply check excessive downwind speed, and prevent folk from getting around the above by a suitable amendment to sailing rules. And, by the way, the whole idea of a rating rule is—and always was—to restrict the excessive size, cost and speed of a class to produce the sort of class that the drafters consider needed. Do you remember before the war when a flaw was found in the A class rule, and if it Just go ahead and design for speed regardless. Add a motor—why not? And a net-catching device, too, (x!) spinnaker, not to exceed twice measured J. (subject to maximum). X To be measured over surface of spianaker with tape measure from X1 to X2 (with a 4-panel spinnaker if a great measurement can be made this is to be taken as X). Y To be measured with a tape measure over the surface of the we proposals 1959 getting cussed by the starter because we were frantically changing it over to the other side (still to be proved wrong half-way up the lake, of course). We should not have to carry four or five around from race to race, and always have the one we needed for a change of wind in the boathouse at t’other end; we couldn’t mislay them either, nor tear. We could get all the speed we need for fine racing by “goosewinging” the jib, and we would greatly ease the labour and strain on the crews in strong winds. From a spectator point of view, the close finish provides most of the thrill for the informed sort of chap, and the other sort can go jump in the lake. And, by the way, experience would tend to suggest that we would tend to increase our intake of new recruits by a ban, for -I know that quite often “possibles” are discouraged from starting by the sheer speed of planing boats, plus the extra complication of the spinnaker lines. It’s just a bit over the odds and tends to put a chap off from starting at all. Where the scoring is 3 out and 2 back, no skipper may complete the 2 in a larger suit (jib, main, or both) than used for the 3. Where the scoring is 2 out and 3 back, a skipper who changes down for the 3 back must remain in that suit or a smaller one still for not less than the next two runs. Where the scoring is 2 and 2 the O.O.D. at his discretion may, or as a result of a simple majority vote of skippers must, declare either “a” or “tb” operative if the wind changes to give conditions which would normally be scored 3 and 2 or 2 and 3, but which must continue to count 2 each way for scoring until the end of the race. For resails taken at end of race We have recently had club races where no-one has put up the things, even though conditions were at times suitable, and everyone seems to have enjoyed it more than ever. One or two of the “experts” have not scored quite as well as usual, maybe that does no harm either, some comparative tyros have done better than usual—all to the good. Two I know have started ; on new craft in consequence. Now do think this over. It is well worth a trial, for if we do not we must restrict the things in size, and also check the boats (a complete ban on spin- nakers would automatically restrict excessive growth by the limit of running ability). 7 fe the conditions which will apvly will be those at the last heat of the race before the resails were taken. Each day (where a race lasts more than one day) and a resumption of racing, where a suspension of more than a half-hour has been caused by climatic conditions, shall be regarded as a “New Race” for the anplication of “ta” or “tb”. This, I must stress. is a draft, for discussion and improvement, but if “changing up for the run” is not stonped then it’s useless to try anything. Just let it all drift until too late. 513 Fig. 2.—Measure to prevent change of kee’s or extension of same in M Class. Measure from A through B and C to D, with tape measu-e and enter on certificate. A D The forward edge of the joint of the keel. The centre of the rudder shipped. bottom (lower) rudder pintle with the MN MODEL MAKER So; if we are to continue to accept spinnakers we must check back on growth by taxing vane and terylene and more drastic spinnaker measuring. We must, you see, do something about the 20 per cent extra sail area (in effect) given by the “newcomers” over cloth and Braine, for the present 10r is in effect a 13 rater; no wonder she is so fast. We cannot go all some folk might think it smart. in Now all this flumdiddle is not really needed. The 1957 winner (I know, for I mated her) and the runnerup in both 1957 and 1959, Gretel (and I know again for sure, for I mated her in °59), has only one keel (fixed) and one top suit. But the writing is on the boathouse wall, and eventually it will be 3 suits top and 3 keels per boat. the way or we shall outmode the present fleet again, sO we must compromise. The taxes below will not greatly upset but will at least prevent continuation of growth, and a pound or two of lead out of the heavier boats afloat will mostly see them right. For the “A” class I would suggest a tax of 45 sq. in. for Vane and 45 for Terylene, a total of 90 if both are used, to be added to sail as measured before taking the square root for the formula. For spinnaker measurement I would suggest: I (hoist), less 4in., in any case not to exceed 60 in. Some simple rule! selves, for all races including the British Open. Others will follow us with gratitude, just you see. were deleted. Just to show how things can go, a very good friend of mine knows of a method of increasing the displacement of a hull by allowing water to enter in a certain way, and removing it as required. He is far too good a sport ever to use it, even though it is legal in a way. I have recently made a little model of a telescopic keel, and it works; taken with the above we could still have a M with a 4in. draught and 3 lb. weight variation, and all variants of same (are you reading, John?) and what an advantage this would be. Let us also stop this sort of hornswoggle. If you will look at sketch 2, this measure, with weight measure (and we already need a tape-measure for spinnakers), entered up would stop all, and so would a “No suit to exceed in any measurement” clause added to rule at No. 1 suit stop more than one tov suit. “And progress?”” JI can hear the wail, but if you object to a one-top-suit-one-keel rule, why do you not object to 50in. loa. and 800 sq. in. sail? You cannot reasonably object to the one without t’other. Can you now? “And don’t attempt to deny it,” as Colonel 10 raters. Tax of 30 sq. in. on both, total of 60, added to Sail Area before formula. Spinnakers, I. less 4in. max. 50in. J. twice foot with max. 36in. X and Y as “A” class. 2nd Suit. I. 40in. J. 27in. x 42in. Y. 18in. 3rd and 4th Dabney said. For Marblehead spinnakers I would be 45 in. max., J. 27 in. x 48 in., and Y. 19in., smaller ones pro rata. Now all this will still be made a mock of if folk are allowed to carry, say, top suit spinnaker with 3rd suit sails, so we shall have to have either a rule en- pro rata. And add to rule, “Models must carry same sizes spars (mast and mainboom) as measured.” The stump for good. 6 Metre. Now, now, before it becomes too universal, let us stop this silly thing. Don’t worry about the “international” status, let us do it for our- J (foot) twice J with a maximum of 40 in. X not to exceed I plus 4 in. Y not to exceed 2/3 of j. X and Y to be measured over surface with a tape measure. (See diagram.) 2nd suit, arbitrary, I. 48 in. J. 36 in. x 51 in. Y. 24 in. 3rd suit, arbitrary, I. 36 in. J. 24in.X38 in. Y. 16 in. And while one is about it, it would do no harm to delete the “freeboard” items entirely from the rule; nowadays they are really pointless (excess in design now pays its own price), and only make more work for the measurer. The same applies to ‘deck camber”. It might enable some of the earlier boats to have a little lead added and make a come-back, which would be all to the good, if the freeboard penalties mast is an added It could easily result a win. complication, let us now sink it Tax of 25 sq. in. on both, making a total tax of 50 for Vane and Terylene, to be added to measured Sail Area before taking square for formula. Svinnakers exactly as 10r, and may be used on either. If the 6m continues to increase this could save quite a bit of cash and trouble, the relative sail areas are so near that this is quite feasible. In the Midlands, where both classes are in use, it is normal to use one’s 10r spinnakers for one’s 6m, and vice-versa. forcing change down when a certain proportion of the entry have changed down for weather (this will have to be used in conjunction with our earlier new sailing rule), so that when, say, half of the starters are using 2nd suits all must use second size spinnakers. or smaller, and the same with 3rd suits. Or a compulsory change down at a predetermined wind velocity, which would entail issuing all clubs with a simple wind gauge (nothing difficult about this, nor even costly). (Our very good friends wi’ Scots’ tongues, aid here.) In view of the trends of design, it is probable that a good third of the 6m rule could be either omitted or replaced with fixed values, and thereby halve the time and trouble of measuring. without in any way upsetting the rule. For the class has “grown uv” the last few years and the rather over-canvassed “forced hull endings” types utterly outmoded. There is no danger now in deleting those parts of the rule no longer serving useful purpose. Marblehead. This is a classic case of too simple a rule. A garboard restriction had to be introduced to stoo the prognathous keel and its children, and now things are about to get out of hand again. It is becoming common for these boats to have 3 top suits (often comnlete with spars), of differing aspect ratio, and 3 keels of differing weights and depths, and though officially the keel must not be changed during a race it is easy to think of ways of doing it, and But you see how much simpler, and much less likely to lead to protest and “you’re another” parties and things it would be to just ban spinnakers, introduce the new sailing rule to prevent. changing up down wind, and leave it at that (though the one keel and one top suit rule would still be good for the M) for all the revisions to spinnaker sizes and ratings would still not be quite as adequate, and much more complicated. A last word on this article (later we may be able to sum up correspondence, and perhaps have a go at the A and 6M revisions, but that is for the future) that wretched little bird is again whispering that registrations are not rising, and overall club memberships aren’t either. So don’t cast the idea away and say “Rubbish”. or I fear that if that is done our boats may be that in a few years’ time—rather tragic rubbish, but never mind, there may be radio control for her so that she can still sail. Alas, however, the spinnaker is banned for this! 514
