Post deleted by twicebitten

Thanks ncik. This is the kind of information I was looking for and will help put my mind to rest the next time an 'A' flies past. However, am I correct in thinking that a slightly narrower F16 could point higher? my last Stealth was 7'6" wide and on occasions did feel to be pointing higher than the 8'2" models although this was probably jeopardising my downwind performance.
Also, what are your thoughts about the F16 upwind performance against the F18. Here in the UK there are some extremely fast 18 sailors who just vanish into the distance but even at Club level I would have thought the F16 has enough in it to make more of an impact. In the light stuff the 18's momentum seems to carry them through the lulls and shifts and as expected when they're twin wiring I haven't much of a hope being single handed. The only saving grace is that at Mumbles Y.C we use Texel so the 'A', F18 and Solo F16 all sail off 1.01 and in the medium wind range the 16 is competitive.

Mark,

Having sailed against a very competitive F18 at Grafham a few times (BUT I was just on the boat so I was making loads of mistakes) I would say the following

1, Light winds the F16 is faster all around the course; this was also shown at the Datcht training weekend when we were sailing around with a couple of guys on a Tiger and I was just just about staying in front of them most of the time.

2, Medium winds Both boats have comparable speeds upwind and the F16 single handed is faster downwind, but they can tack and gybe quicker. The age old problem that the single hander runs out of hands and I was new to the boat. Thus, I need to get better "around the boat".

3, Strong wind. I was making more mistakes, but I could almost stay with them upwind (Max DH, traveller out about 18 inches, plates up about 18 inches) but they were faster downwind as I was not wiring - again more practice in the boat to be able to wire in more wind downhill.

I believe we should still be aiming to be in touch with F18's and "beat them on our day". We will struggle as there is a very great depth of talent in the UK/world F18 fleet. If you were to put yourself into the F18 fleet, where would you put yourself ? Top 20 maybe at the worlds, I bet no 20 is 300+ yards or 30 to 60 seconds behing the winners at the end of a 1 hour race.

Aren't we going a little bit over the top here ?

This guy does ALOT of development and pays for it out of his own pocket. Most of it has already been incorporated into the new boats sold.

He has expressed his desire that his endeavours be kept confidential till his testing has been completed. I think that he has a full right to desire that considering in how many ways he is advancing the F16 design on his own.

This desire is not the result of being unsportsman like or whatever, but by garanteeing a quick and free flow of development. Lets face it, nobody wants a crowd looking on their fingers when they are experimenting. 3rd party suppliers are hesitant to participate if such development projects are scrutinized in public.

Personally I think it to be bad taste by the others if they can't wait a couple of months till the experimenting has been completed.

I'm sorry, but I think some of us are reacting like little children here.

Wouter

Hi Wouter,

I have Deleted the post as I had a PM from the sailor and I had the wrong end of the stick. I didn't realise who you where talking about <img src="http://www.catsailor.com/forums/images/graemlins/confused.gif" alt="" />. Would probably been better if you had said nothing, than to start talking about it and go no further.

No offence intended.

Well yes, It would indeed have been better if I had not written that initial paragraph :

"Also we are losing some upwind performance because of the spinnaker package and the spi halyard running up the mast. I saw a good trick on a singlehanded F16 recently. The owner had moved the spi halyard so that it run up along the forestay instead of along side the mast."

Sadly I was too late to delete it when it became clear everybody was falling on it like a pack of starved wolves.

My mistake definately. I just wanted to point out that the F16 can go some way in optimizing the rig just as the A's have done over the last 30 years. Naturally each improvement will be very small but when you add up 30 years of it then the combined total can be quite large. We F16 sailors have only been at it for 6 years now.

My appologies to everyone. I should never have written down this example.




Alright, everything is fine now.

Wouter

Pointing ability is a tricky topic. It has a lot to do with sail shape, ability of the hull to be driven, conditions, foils, etc...

Righting moment is not just about hull beam, crew position is also critical. In the marginal stuff, maybe you could try sitting in off trapeze and flattening the sail shape, point a fraction higher, taking the form drag out of the rig...see what happens, it can't hurt to try it. Then again, I could be talking out of my butt, I'm just throwing up ideas here.

The best option is to find a similar boat with similar speed and do some two boat tuning. There's plenty of resources online to help develop a good testing regime. One day of useful two boat training will bring boat speed results, maybe even to the point of chasing that pesky A-class.

I had a great time yesterday afternoon chasing a farily new Tornado around the Bay. We did a 2.5 mile run on port then another 1.5 mile run on starboard and there was nothing between us apart from the fact they were both sitting in and I was on the wire. Upwind, astonishingly they were pointing higher but I was going lower and faster so after 2 miles I was in front (No Bulls**t) Needless to say I was quite pleased with the way things were going.
What I do want to experiment with whilst two boat tunning is the Mast rotation in light wind conditions, as people around here are talking about having the spanner pointing at the intersection of the rear beam and hull. In other words a lot tighter than I would normally have it.

Mark,

There ARE 2 schools on mast position in light wind. Pointing as you say above, or fully rotated along the front beam. Needs 2 boat tuning to sort it out.


Also, just remembered that Haken had a kite on his A class as said the thinks it cost him about 2%ish upwind with all the extra gubbins floating around. Then factor in the extar windage of the 16, longer slimmer hulls on the A class, I think I'd be happy with a 10% difference upwind.

Would be interesting, did the OOD at the Nations cup record Lap times. I was catching up the A's on the first race (must remember to count laps). IIRC the last lap there was much less wind on the last run which kinka skewed the results to look at with the extra lap.

>> did the OOD at the Nations cup record Lap times.
>> I was catching up the A's on the first race (must
>> remember to count laps).

http://www.mumblesyachtclub.co.uk/results/2007/200705af16.htm

We do have lap times but they are not published - I could get them if you want...

Edited: I misread SSs post.

Colin,

I mean laps not races. In the first race I was about 400 yards ahead of Dave and on the last lap, I think I was stating to tag onto the back of the last A's.

I'd really like to see individual lap times for Race 1 if they exist. In fact looking at the results this is partly shown by finishing times. Yvonne did 4 laps (and last A class to finish) and finished at 13:29:13, I did 5 laps and finished at 13:29:55; Dave Tugwell did 4 1/2 laps (ish)and finished at 13:29:25. But the last lap for me was by far the slowest. This is the info I'm after if it exists.

Yeah, I misread your post - I'll dig them out.

Thanks Colin,

The A's were generally smoking us anyway. But the first race was the race I was sailing best and did not make to many mistakes.

Most of them were smoking me too <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />

John and Mark,

I try to look at the re-routing of the main halyard with a neutral position.
1: The Tornado fleet dont invent everything, as their creative pool is limited to fleet members <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" /> and reliability is a concern.
2: The Shearwater dont look too fast (I would not know) by the photos on their website. Looks like they have centerboards not daggers and the hullshape is kind of V'ish. Would the relatively small difference in drag/lift be noticeable on that platform?
3: 2.5 to 6 minutes delta upwind is a lot, and so it's worth researching now that the horse is out of the stable.
4: Shearwater assocs. website crashes my Firefox every time <img src="http://www.catsailor.com/forums/images/graemlins/mad.gif" alt="" />


I got to say, if I were planning a really secret weapon for a major event, I would also like to keep it quiet. But then again, I would not go racing with it. Two boat testing is the way to go if you want to keep something hidden. The openess is partly what makes this forum so cool.

I suppose the increased pitch resistance from T-foils (like the ones Darryls F-14s use) could help neutralizing the advantage of the A's longer hulls upwind.

Mark, good of you to kick some Tornado butt. Got to say tough that the boat is not easy to get the most from. Sailor skill makes up for so much speed on the boat.

One question. What will 20kgs difference in crew weight do to your pointing ability? How about 40kgs?

Second question. How many go low after a tack to build virtual wind before heading up? Is it worth it?

Question one; I can't answer as I don't have a crew of any description (Unless 20 Marlboro lights count)
Question two; When it's windy I stay very high after a tack until I'm safely out on the wire and then bear away to a proper course. In medium winds when I'm not aiming to roll tack it's beat to beat or as close as I can judge it. In light winds I don't move across the boat until it has tacked completely and has started to make headway on the new course. slightly lower than normal as the main has been dropped off, the new windward hull often lifts and at this point I'll move over (mainsheet at the ready just in case). I find using this method of tacking doesn't upset things as much as moving over when there is no wind in the sail.

Rolf,
Try updating the Java on your computer, that might solve your FireFox problem.

The Shearwaters aren't particularly fast, that's true, but they've been around a verrrry long time and have quite sophisticated rigs (there was at least one square top main in regular use back in the late '70s).

They had very slender wing masts with 3 sets of spreaders and airflow was critical. I notice that the more recent boats have masts more similar to the Tornado section. I should think that, being a development class, they've experimented with just about every combination of sail control and routing imaginable!

Interesting then that a lot of the 'top' boats still have a pretty 'standard' layout that is comparable to most modern cats. The Shearwaters even had curved tracks before the 'As' !

Allow me to set the record straight, before anyone misunderstand me and think that that lead was caused ONLY be rerouting the spi halyard.

Alot more was tweaked on that boat then only the spi halyard and it was a club race. The skipper sailed well and his adjusted his rig the best in the changing conditions. It went from light to strong winds over the course of 2 heats and 7 laps. Most of gains were surely from sailing well and not making large mistakes. All this combined with his sailing skills (=good) caused the outcome.

In the second race the rest of the fleet got their acts together and the lead was shrunk to 2.5 min. This weekend we'll see the next installment and all the other boats will have had a few more sails as training down their belts.

So all is very preliminary although I really tried and simply could not hold on to him upwind. I could with respect to the others in the fleet. I would have loved to have his upwind performance.

Wouter

Curved tracks even with a spi? What would the advantage be unless the boats dont build much apparant wind when going downhill?

I got the impression that the impressive deltas to windward was down to the re-routing of the halyard. Now it's sailor ability and a series of improvements. Not sure what to belive <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />


John, I dont think it's Java crashing Firefox. The applet they use for navigation works well enough, but there is some kind of silly Javascript/DHTML 'transitions' in use:

Javascript is a can of worms, and DHTML and abomination..

Rolf,

What version of FF are you using and with what plugins ?

http://www.shearwater-asc.org.uk/ works fine for me on FF 2.0.0.3.