3rd Gear: Overpowered while double trapezed

[ALutz]

Hi all

I just wan't to share some experiences and hope we all gain more speed!

We were fast in light to moderate winds, until upwind driving the '3rd Gear'. So for us, this is our 'problemzone'. we are a very light team (~130 kg / 260lb) and are sailing with the Landenberger main and gennacker.
The Landy main is very powerfull, and when trimmed right, very fast! The sail works only in a small window, witch we missed, when driving in the '3rd Gear'.
We followed Peter's '3rd Gear' guidelines and still got not enough speed. The boat feld slow and was hard to control, despide pulling the cunningham (16:1) very hard. After several phones with Landy, the problem was found, we rotated the mast to far in - 'low drag mode'.
He said, his sail is not designed, to be driven with a fully inrotated mast. The mastrotation should not go below 45°. Sideflex on top of the mast is not desired, as this will close the afterleach.
The too far inrotated mast, caused that the mast lost his flexiblity to bend afterwards and to react on the mainsheet tension (despite we pulled the cunningham very hard).
It was not obvious for us, as the mainsail allways looked flat as a board. We changed our rotation setting now to 45° and plus, traveller a few cm's out and what a differenz!

Here is what peter's tuning guide says.

3rd Gear: Overpowered while double trapezed

• Tacking angles at about 80 degrees.
  
• Mast rotater should be aimed between the back of the daggerboard trunk and the aft beam end. The mast should bend sideways to leeward at the tip.
  
• Cunningham should be pulled on until you do not have to play the mainsheet so much. Let the mast tip do the bending in gusts.
  
• Outhaul should have 2” of depth at mid boom
  Mainsheet should be eased in gusts. When sheeted tight in lulls, you should be at the perfect power. If still overpowered, pull on more Cunningham. If underpowered, ease it off some.
  
• Helm and crew on either side of the side shroud. In big gusts, move back 3-4”. In big lulls, move forward 3-4”. If you ever crack off, move back 2-3’.
  
• Footing is fast, and luff tell-tales flowing straight back. For teams weighing under 300 lbs, it can pay to go into total pinch mode with the main strapped in. If you find you do not have a ‘low and fast mode’, this can be effective until you sort out how to put the bows down and jam.
  
• Basically, the sail is in fully depowered blade mode, and the mast is in low drag mode.
  

So let's get faster!

Greetings from Switzerland

[Peter J]

Interesting info above. I wonder if this is because the Landy main is too full? And more rotation is the only way to get it to flatten? If you are so light, why not try a sail that flattens out with the cunningham and sheet tension?

Glenn Ashby has been helping me with advice to get going with my new A-class. Thought you might enjoy seeing what he writes about the rotation on an A-class....which should directly translate to the 18HT:

TEXT

I'm not sure I'll ever have the cooridination to play the rotater in each tack! But interesting advice on rotation from the World's best una-rig sailor.

[Peter J]

Sorry, something happened to my above note. Glenn Ashby's advice:

Up wind up to 10 kts about 45 to 40 degrees.

Up wind 10 to 15 40 to 30 degrees

Up wind 15 kts plus 30 to 20!

Basically up wind as a rule of thum, I pull the mast in until the lower leeward mast telltail almost wants to stall and then let out about 5 degrees, A good trick if it is not real windy but enough to use a fair bit of cunningham is to drop the rotation out about 15 degrees just before the tack or just as you cross to the other side as this dramatically helps the re-atachment of flow around the sail at low speed and out of the tack. Especially when the boat is taking its time to wind up out of the tacks when it is marginal traping conditions.

As you climb out on the wire as the boat picks up speed and the apparent wind builds, the mast can be then brought back to the original setting.

[ALutz]

Hi Peter

Thanks for posting the advices from Ashby!!

I'm using basically the same setting's on my A-Cat to. There I have a Godall AR4 witch is full to.

In the talk with Landy, I mentioned this too. But he explained to me, that our masts (Bimare, Ventilo and especially the Marstroem masts) are mutch stiffer in the longer diameter direction than the one's used on the A-Cat.

>If you are so light, why not try a sail that flattens out with the cunningham and sheet tension?
The Landy main is not too full, the reason why it is so powerfull is because, the after section of the sail is still a bit curved. It is designed to be driven with a bit of twist. It is basically the same sail, he is using on the tornado. And the sail should be specially fast in higher winds.

Here you can see the sail with not enough mastrotation (it's a link)

[Peter J]

That sail looks deep and full. Maybe try some more pre-bend?

[ALutz]

The picture of the sail was taken when there was not allot of wind.

It can actually be pulled flat as a board. Our problem was, that we didn't have enough speed. I have tried more prebend before, but not systematically and with out success.
All I can say the boat is moving now better, with more mast rotation. Maybe it is just a mather how the sail is designed and could change from sail to sail?

We are going the next two weeks in vacation to the lake of garda in italy. There we should have good winds to try different settings!

Thanks again for your input!
good sailing

[Bob Hodges]

Another control you may be failing to use is the mainsheet traveller. If you have your mast setup right, rotation is correct, max downhaul, and you still feel you are not fast forward, drop the traveller in 3" increments. It is amazing how that can improve your speed. We do it in A-boats at about 14 knots of wind. In the 18HT, the break could be around 12 knots dependent upon your crew weight. This is much better than easing the mainsheet.

In a recent long distance race which had a 14 mile upwind leg, the wind was blowing 14-16 knots. I was sailing my A-boat and dropped the traveller about 4" from midline. This "quieted" the boat to the point where I was only playing about 6" of mainsheet and could focus on hiking and steering. I blew away the I-20's, H-20's, and NACRA 6.0's that were also racing with me (more speed and height).

Remember, the faster forward you go, the more lift your foils produce so focus on doing whatever you have to do to keep the bow down and flying.