Telstar tender

[Marina]

Ok, so i'm a new telstar 8m owner and wanted to hear the forums advice on tenders, particulary the weight issue and how much it seriously affects sailing performance. Firstly i should say that previous to the telstar i and the family are from a powerboat background with waterskiing and other toys high on priority. When i chose a telstar over other trailer sailers it was largely due to the large deck space and its ability to take a fair sized inflatable and engine packed up for voyage. As much as we wanted to get into sailing and cruising we didnt want to give up the toys altogether so we want an inflatable me atleast 3m that can take atleast a 25hp for skiing etc. We are looking now at a zapcat which for those of you unfamiliar with them are a 4m cat inflatable with a 50hp 2stroke outboard. The boat can be completely folded up to a small size and weight of 75kg. The engine weighs 70kg. I realize that the assembling and etc would be a real struggle, but we plan to mainly tow it and deflate and put on deck (outboard secured to one deck and boat to other) for longer voyages. Now i see on here that there is a lot of talk on here about the issue of excess weight aboard and towing and how it affects sailing performance. Would it really be that big a issue? When onboard it would be the equivalent of one small man standing on each deck and when towing the area of boat in the water is tiny, so minimal drag, and the boat is built for extreme rough stuff and has a self draining transom. I should also mention that we are not looking for top sailing performance and would not be too upset if the boat were a little sluggish.... Thoughts?

[Ron]

I should also mention that we are not looking for top sailing performance and would not be too upset if the boat were a little sluggish.... Thoughts?

You answered your own question. As long as you distribute the extra weight somewhat equally side to side and bow to stern, it won't really hurt
the boat in the water, up to a point. But it will slow you down. Remember that you're sailing a "light weight" 4500 pound boat, and 500 pounds is adding about 12 percent to the weight. On a 25,000 pound boat it would be nearly negligible at around 2 percent. As far as drag goes (with the tender in the water), note that keeping the Telstar's Honda motor in the water is probably worth over 1/2 knot of boat speed, so the tender will do even more.

500 extra pounds could hurt trailering as well. The tires and brakes would be overloaded. Note that the two drum brakes are overloaded already. Maybe put them in the truck instead.

Since 2 people is more than enough to handle the boat, I try not to race with 3 on board. The extra 175 pounds or so will only slow me down. I'd race single-handed if they'd let me. I think I must lose close to 1/2 knot per crew member.

[Dan]

I’d point out that the trailer may have brakes on both axles, as this is an older Telstar 8M not one of the Telstar 28s with a Venture trailer.

Also, if you have to load a lot onto the boat, you'd be best off loading it slightly aft-heavy, rather than equally fore-and-aft. One key thing for multihulls is to keep the bows buoyant as they will do a lot better that way than if the bows are heavy. This also helps prevent the boat from pitchpoling, since the bows are far more likely to rise with the waves, rather than get buried and dig in.

[Marina]

Thanks guys. Ron, I believe the conversion to lbs makes it around 300lbs rather than 500, so not so bad. I intend to transport in the tow vehicle, not in the telstar, although the trailer is plenty capable at 3500kg gross,braked all round etc but the tow vehicle would struggle if it was anything near that...
Dan, you're right it is an older 8m and has a new massively specd trailer. You surprise me with the view that the boat should be loaded stern heavy. The previous owner has told me to do the opposite, and certainly from my previous experience with powerboats, you always get better performance and less pitching with weight forward. My telstar has had a plum bow modification, so either way, hopefully the pitching will be minimal

[Ron]

Dan's right. I'd aim for about 60 percent (maybe a drop more) towards the stern and mid-beam if possible. But in your case it would probably wind up on each ama. Multi-hulls prefer to pitch-pole than flip sideways. Didn't realize it was an 8m either. Do you happen to know the real weight of the boat? The 28 comes in at around 4500 pounds, about 1,000 pounds over spec.

[Pat Ross]

8M Designed Displacement, which is the boat plus payload is 2800lbs, 1270kg. I will weigh mine on the trailer late summer and then luanch and re-weigh trailer and report findings. Ofcourse the models who have done extensions would have to recalculate by re-weighting empty to figure the Design Displacement.

Pat

[Ron]

Pat -

The designed displacement of the 28 is either 3000 or 3500 pounds, depending on which brochure you're reading. At 4500 the boat is nowhere near either. I'm sure that you'll find that you're significantly heavier than the specs as well. Every boat I've ever seen is heavier and draws more water than what the designer predicts. All they have to do is weigh and dunk it after it's built and they'd see their error. I've owned, sailed on, or delivered a number of Catalina's and the bigger ones seem to run anywhere from 4000 to 6000 pounds over. Hey - my new (to me) 2007 ComPac Horizon Cat is about 800 pounds more and that's only a 20 footer!

I don't know what they are ALL trying to accomplish with their mis-leading specs. They are all either not-too-bright or are too lazy to figure out what they are actually selling. I've actually seen the VP (and designer) of a major sail boat builder at a boat show cross out the draft and write in a number 6 inches less when he overheard a prospective buyer say that it draws too much water for his location. I wouldn't want to be on that boat when he launches and runs aground 2 minutes later. The original draft was already about 3 inches too low. I think I just answered my question - their goal is to sell boats.

[Pat Ross]

Ron,

I know you are right on there, but until I verify the inaccurate data, all I have is the brochures and a few books that report the data. I have been trying for years to get actual data
on all multihulls and then develop two data bases on Multihull Dynamics, Inc. One database being the designers/production builders reported data and then the actual measure database. But this requires help from owners to develop such a database and thus far I have found very few people who are willing to do the work necessary to develop such a database. I have thought of contacting large marinas that do a lot of multihull business to see if they are logging the crane weights of the boats they are hauling but have not yet done that. One of the problems of course is ensuring that the crane would be calibrated to give an accurate reading prior to hauling the boat.

I also think owners are sometime reluctant to give data that they fear may make their boat appear less than advertized. I think the sooner we did this the sooner we would get accurate information in marketing.

So for me I am going to weight my boat empty and weigh all the gear I put on it. Measure the boat from stem to stern, port to starboard, including the sails, leave nothing to chance, get all the accurate real data I can, rerun all the formulas and report the results.

Pat