Fastest dinghy?

I am sure nothing goes as fast it felt the first time I got planing as a middle aged beginer back in the 1980s in an Albacore with clubmate Graham Parker giving me a few tips off of Teignmouth beach.   That felt supersonic!  My jaw nearly fell off from the width of the grin!

I shall remember it till I die!

Fast is when its all on the edge of control!

Blasting dead downwind in 50knots won't do it. You've got to have apparent wind. Think about it, if you're doing 30 knots dead downwind in 50knts of wind, then you only have 20knots across the deck. Then also if you gat a 10 knot gust followed by a 10 knot lull - and 20% variation in gusts seems to be reasonably common according to Bethwaite - you'll suddenly have variation between 10 knots and 30knots. Unless you've got the apparent wind forward of the beam then the faster you go the less wind you have across the deck.

So you have two choices for speed, one is very high efficiency with the wind forward of the beam - Yellow Pages Endeavour with 48 knots of speed in 20something knots of wind - and the other is more moderate apprent wind and very high wind speeds coupled with guite amazing control in gusts and lulls - the top board sailors.

And again look at the sail size they carry - http://www.sailspeedrecords.com/500.html. The boards have all hit their records with under 10sq m of rag. YPE was damn near as quick with their class B (150-235sqft) rig as with their Class C (235-300 sq ft) rig. I bet that big rig was nowhere near 300sqft, and they didn't even have a over 300 sq ft rig and the record for that class is even slower. Even a Cherub or 29er rig is damn near the top of class C, let alond a 49er or a 14.

Then you also have to think just how difficult it is to get a high average speed. Take a look at this bit of video. Its of a Cherub with a development rig going quite reasonably quickly in a fair breeze. Now look closely. See how much the speed varies? Look at the bit where they run out of the gust and have to point up and so on. Chances are to average 25 knots over 500m travelling like that you've got to be peaking out at over 30. Also shows how much apparent they were carrying when they have to head up that much when it evaporates.

WHy are there no measured speed records for modern dinghies. Two reasons I reckon, one its a lot of hassle to organise, and two, too many "big fish stories" would die with the results. I think a 14 did speed week recently and got a best result in the mid teens. I've considered doing it, but its quite a lot of cash and holiday to sit on the beach all week hoping that one day the wind will get up enough to make some runs worthwhile, and probably even then finish with something ike 16knots as your best time.





Edited by JimC

Originally posted by Scooby_simon That cherub is not going very fast at all....Low teens I would say....

The variation in speed is the point I was trying to make. Its why GPS spot speeds are very different from timed 500m runs. Because I only got that as a WMV file I can't do any analysis of how fast its going by frame counts, but I don't think its anything very dramatic.

As the question was about the fastest dinghy sailboards and catamarans get disqualified immediately. Sailboards are fast because they are very light and the sail control is far easier with a tilting rig. Catamarans are fast because they have enhanced stability making sail control less critical. (though I suspect that in a speed trial the stability vanishes as they will work to stay on one hull).

Although I agree some smaller dinghies can go out in bigger winds than their bigger cousins I doubt they would go absolutely faster. I think the secret is to make hay while the sun shines. With lots of efficient sail on a light, easily driven hull you can get up to a respectable speed before the natural turbulence in the wind gets too much to handle. In the summer I watched a 49er on flat open water in just a force 4 outpace a powerboat over about a mile, while looking like "just another day at the office". I think that a smaller dinghy is unlikely to achieve as much in a bigger wind.

However, what counts for the everyday sailor is the excitement and the perception of speed. For me, the peaks were a Laser 1 reaching across the bay at Abersoch in a force 6 gust with the hull chattering over the chop and a Laser 2 two-sail reaching at a world championship in force 6-7 with the crew trapezing behind me. I'm sure every other sailor has similar perceived highs, none of which would make the speed record books.

Hagar

PS - Fizzicist should calculate the rate of rotation of the eyeball as it watches the nearest stationary point, multiply by the wind speed across the face and throw in a factor of the generated noise. Big wind * close to the water + (shrieking wind * spray) = exciting. 125mph in modern train = nothing.

Its the go-kart effect, 10 knots+ on a topper with your bum on the surface feels a lot faster than in something with a lot of freeboard like a 200 or bigger still a yacht (having said that 10-15 knots feels pretty quick in most yachts beacuse you only get that surfing in a big breeze). 

The way I see it is if you survive a day on the water then you've played mother nature and won!!  If you win a race, even better, and if it feels fast than it is!!