Confused by race boat speeds and boat handling

[meirriba]

Originally Posted by Jim Cate

Actually, a lot of folks call what you are describing as "tackig downwind" when they are actually gybing all the time. The name isn't important, but the act of sailing higher angles rather than DDW does work for many boats. And for those that can reach higher speeds, it really is tacking!

Jim

Sure Jim. I can do it on the Nacra (which sail over 150% of wind speed) but could never do it on the Lagoon.

[donradcliffe]

This year I started racing a Manta landsailor , which has similar performance to the AC 72. Typical speed when going to weather is 20-25 knots. Rounding the weather mark, you need to ease the sheet slightly as you bear off (or you will flip), then pull it back in as you accelerate to as high as 50 knots or more. As the speed increases, you can bear off more, but if the sail starts to luff its more likely that you are too low than too high. When you gybe the apparent wind moves through the front like a tack.

The other weird thing is that you overtake the gusts when you are running.

There are much faster landsailors, but the Manta twin sells new for less than $3k, and there were 52 Manta twins and 22 singles on the line at the world championships this year in Nevada. Great fun!

[Jim Cate]

Originally Posted by donradcliffe

This year I started racing a Manta landsailor , which has similar performance to the AC 72. Typical speed when going to weather is 20-25 knots. Rounding the weather mark, you need to ease the sheet slightly as you bear off (or you will flip), then pull it back in as you accelerate to as high as 50 knots or more. As the speed increases, you can bear off more, but if the sail starts to luff its more likely that you are too low than too high. When you gybe the apparent wind moves through the front like a tack.

The other weird thing is that you overtake the gusts when you are running.

There are much faster landsailors, but the Manta twin sells new for less than $3k, and there were 52 Manta twins and 22 singles on the line at the world championships this year in Nevada. Great fun!

Don, that sounds like a lot of fun for the bucks! Ice boat speeds (almost) without freezing your ass off!

Where are you sailing this thing?

Jim

[daddle]

Originally Posted by meirriba

The original poster claimed that his cat was routinely tacked downwind...

No, I doubt very much anyone here has ever truly tacked on a downwind course. Cruising cat or racing cat. The sails may have performed what appeared to be a tack but the wind did a gybe. Maintaining speed thru the tack must be a trick, as evidenced in the AC races. Tacking a lightweight cat *upwind* is non-trivial.

[goboatingnow]

The sails may have performed what appeared to be a tack but the wind did a gybe.

If the apparent wind, passes through the bow, then its a tack. Its matter not a whit what the true wind is doing, since that really doesn't exist.

[Sailmonkey]

Originally Posted by meirriba

Thanks for the explanation...
The original poster claimed that his cat was routinely tacked downwind and I wondered. If he has an AC boat than fine.
,

You and I may have read different op's then. I have a brand new f16 beach cat and it doesn't approach downwind tacking, the wind is fwd of the beam when downwind reaching but that changes rapidly once the gybe has begin.



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[sailr69]

I had sailed DN60 for a few years and every leg is a upwind sail after you get the boat moving. tacking upwind, yes if you use true wind. true wind means nothing in a DN 60, except to get the boat started. 50 to 60 MPH in 12 knots is normal. cold? you bet. but a real hoot. use snowmobile gear. biggest problem? finding good ice. there is a network for the best ice. Lot of road time anymore with the warming of the planet


DN 60 ( Detroit news. 60 sq. feet sail area) winner of a iceboat design contest

[donradcliffe]

Originally Posted by Jim Cate

Don, that sounds like a lot of fun for the bucks! Ice boat speeds (almost) without freezing your ass off!

Where are you sailing this thing?

Jim

The worlds were at Smith Creek dry lake, 3 hrs east of Reno, while the next big race is at Ivanpah March 21-28, 2015--just outside Las Vegas. They also sail at El Mirage near Lancaster, California.

The learning curve is pretty steep--I finished mid-fleet, and was always nearly last at the windward mark.

For more info see NALSA's landsailing home on the web.

[daddle]

Originally Posted by goboatingnow

If the apparent wind, passes through the bow, then its a tack. Its matter not a whit what the true wind is doing, since that really doesn't exist.

Yes, obviously. But the apparent wind does not necessarily "cross the bow" during what someone might imagine is a downwind tack. The wind is certainly forward on one side before the maneuver and then (long) after the maneuver forward on the other side, and one did start the maneuver by turning toward the apparent wind, but as was pointed out above the apparent wind goes well aft as soon as the boat slows thru the turn. It becomes a gybe. Unless one has an extreme cat, which nobody here does as far as I can tell.

[barnakiel]

Just like ice-sailing. You are full time beating.

b.

[thomm225]

Originally Posted by marinduque

Yes, obviously. But the apparent wind does not necessarily "cross the bow" during what someone might imagine is a downwind tack. The wind is certainly forward on one side before the maneuver and then (long) after the maneuver forward on the other side, and one did start the maneuver by turning toward the apparent wind, but as was pointed out above the apparent wind goes well aft as soon as the boat slows thru the turn. It becomes a gybe. Unless one has an extreme cat, which nobody here does as far as I can tell.

All the F Series Beach Cats still gybe but can reach speeds in excess of 25 knots. When you sail thru the gusts downwind with the spinnaker up, it's just a slight steering adjustment low or high very similar to upwind. (but if you are tired and steer the wrong way then you pitchpole and can break stuff)

The spinnakers though are getting VERY flat much flatter than used to be used on the Nacra 6.0. The 6.0 is an awesome beach cat though because it's heavier than most. (And) it slices through the water as if on a rail unless it's very, very rough. (mine was sail number 225 btw) The 6.0 makes it easier on older sailors because it takes the beating not the sailor so much.