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rom · 14-02-2018, 02:18

Quote:

Originally Posted by arsenelupiga

one day in the future, when you start ignoring what CF experts say, you will experience yourself. But if you do not go down to 30, 27 app you will never know.

One can easily with lagoon do <90. You need say steady 20 kn true or more, full sail, and flat water. Instead of reefing, you decrease tacking angle.

On your surprise you will start going faster than monos, and better angle. This will hurt some egos around you. And boat will be happy. And you will see <90, assuming no currents.

I was teasing you arsenelupiga, don't worry I know about CF experts.

As I said in my first post there are many factors internal or external to the boat that would sure help make better than 116° tacks over ground, which is someone my best. But really 90° seems impossible to me. I would love to be proven wrong, please show me a track

arsenelupiga · 14-02-2018, 02:39

Quote:

Originally Posted by rom

I was teasing you arsenelupiga, don't worry I know about CF experts.

As I said in my first post there are many factors internal or external to the boat that would sure help make better than 116° tacks over ground, which is someone my best. But really 90° seems impossible to me. I would love to be proven wrong, please show me a track

i cant show you my track because of currents, i dont bother capturing them. Could show you 70 deg but that is not real.

However, here i found for you review of L 400 by monte, very experienced cat sailor that has sadly passed away. he actually alerted me that lagoon can go upwind at better than 50 app. these days i listened CF experts.

http://www.cruisersforum.com/forums/...ml#post1824497

relevant bit copied out:
----------------
Boatspeeds upwind are close to half TWS, up until about 8kn speed through water. After that its better to pinch a bit or reef as the apparent wind will be over 25kn. We've since had some nice upwind sails and tacking through 90 degrees is quite doable while maintaining good boatspeed, say 7kn in 16kn TW, giving an upwind velocity made good of around 5kn. -

DavefromNZ · 14-02-2018, 02:59

Lagoon 450, after trying everything, for 6 years, the upwind angle is 60 deg TWA. No more nor less in zero current.

44'cruisingcat · 14-02-2018, 03:05

Quote:

Originally Posted by rom

I was teasing you arsenelupiga, don't worry I know about CF experts.

As I said in my first post there are many factors internal or external to the boat that would sure help make better than 116° tacks over ground, which is someone my best. But really 90° seems impossible to me. I would love to be proven wrong, please show me a track

If you sail slowly enough in strong enough wind, you could get just about any boat to tack through 90', or close to it.

Strong wind and low speed makes for small differences between TWA and AWA. So if a boat can sail at say 40' apparent or better at low speed, you could quite possibly tack through 90, or even less.

44'cruisingcat · 14-02-2018, 03:13

Quote:

Originally Posted by rom

I was worried you were about to tell us about the perf of your own racer ! ok, that is very good, and though not as good pointing as the Lipari's polar, it may be as good a VMG, but we you don't say about TWA. L380 is quite a bit shorter so I suspect you had good sea conditions.

TWA would be about 48', VMG about 5 1/2 kts. Fairly sheltered water.

rom · 14-02-2018, 03:27

Quote:

Originally Posted by 44'cruisingcat

If you sail slowly enough in strong enough wind, you could get just about any boat to tack through 90', or close to it.

Strong wind and low speed makes for small differences between TWA and AWA. So if a boat can sail at say 40' apparent or better at low speed, you could quite possibly tack through 90, or even less.

Yes I totally agree, this is mathematical. However as I said my AP will start doing mistakes if set below ~38°AWA, and my boat is so fast that 38°AWA translates into 60°TWA

Seriously, I would have to hand steer to point better and reduce the speed. That would theoretically improve tacking angle over ground but in practice would induce more drifting. All in all I don't think this would make for a better VMG.

rom · 14-02-2018, 03:30

Quote:

Originally Posted by DavefromNZ

Lagoon 450, after trying everything, for 6 years, the upwind angle is 60 deg TWA. No more nor less in zero current.

Only 2 years for me, I am still open to suggestions

rom · 14-02-2018, 03:32

Quote:

Originally Posted by 44'cruisingcat

TWA would be about 48', VMG about 5 1/2 kts. Fairly sheltered water.

Any idea how that looked over ground ? 48x2 + drifting ... 110° ?

44'cruisingcat · 14-02-2018, 03:39

Quote:

Originally Posted by rom

Yes I totally agree, this is mathematical. However as I said my AP will start doing mistakes if set below ~38°AWA, and my boat is so fast that 38°AWA translates into 60°TWA

Seriously, I would have to hand steer to point better and reduce the speed. That would theoretically improve tacking angle over ground but in practice would induce more drifting. All in all I don't think this would make for a better VMG.

Wind strength should make a big difference to your tacking angles. It certainly does with ours.
When it's over 20, and we're reefed, and sailing at about 1/2 windspeed our tracks start looking pretty good.

44'cruisingcat · 14-02-2018, 03:42

Quote:

Originally Posted by rom

Any idea how that looked over ground ? 48x2 + drifting ... 110° ?

Yeah probably about that.

Scaramanga F25 · 14-02-2018, 08:49

What you have measured is only applicable to your boat's rig setting and
its sails.

Having at one time raced with factory teams loaded with internationally known champions and also with the best sailmakers in the world on board,
I discovered what only they can do and see.

Hans Fogh, Eric Duchemin, Ted Hood, and also the Beneteau factory team loaded with 12 meter crew. Amazing.

rom · 14-02-2018, 10:38

Quote:

Originally Posted by Scaramanga F25

What you have measured is only applicable to your boat's rig setting and
its sails.

Having at one time raced with factory teams loaded with internationally known champions and also with the best sailmakers in the world on board,
I discovered what only they can do and see.

Hans Fogh, Eric Duchemin, Ted Hood, and also the Beneteau factory team loaded with 12 meter crew. Amazing.

Of course you're right, as I mentioned a pro racer would do better than me on my own boat. Should it be for that purpose what I am reporting here is the performance that fellow cruisers might expect from a cruising boat loaded for full time live aboard, by a cruiser (me), in cruising mode. Otherwise I would have posted that on SA

rom · 14-02-2018, 11:46

For those interested here is a new track and a few more thoughts !

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Like yesterday, full genoa, one reef in main sail. It started pretty good with 20 to 24 kts AWS which is the sweet spot (per Lagoon recommendations), unfortunately the wind slowly died to 10 12 kts AWS. The ride was rather smooth with 60cm swell/chop, longer bigger swell in the end.

Unlike yesterday I was a bit more dynamic with the AP and believe I did overall 36AWA as compared to yesterday's 38AWA. Especially with stronger winds in the beginning where I tried to keep boat speed below 7 kts. (funny to say that)
Also I started the track after stopping the engines, and stopped the track before lowering the sails.

As you may notice, the wind direction is not stable, but I have been "beating" all the way, so we may accept an average perf upwind from start to end.

New thoughts:
- if someone cares to share a track (which I hope will happen), it's got to show at least say 4 tacks be taken seriously.
- the one tack that I highlighted on the track is the best with an impressive ~100° over ground. Probably got lucky with changing wind direction here.
- from start to end of the track, VMG is 12.2 NM / 4 hours = 3.05 kts. Which compared to about 6 kts average speed makes an average 60°TWA, or 120° over ground, once again ! (cos(60°)=0.5)
- However the last leg totally ruins the VMG: so if you allow to cheat a little, at the point of last tack average speed was 6.15 kts on the track, time enroute was 3.35 hours. VMG is 12.3/3.35= 3.67 kts and arccos(12.3/3.35/6.15)=54°TWA, or 108° tacking over ground, much better !
- I computed the angles of all 9 tacks, very approximative I admit, the average over ground is: 117+120+112+100+111+111+100+103+117/9 = 110°. Which is quite in line with the 108° above.

Conclusion of the day:
- It would be very easy for the marketing department to show nice numbers.
- Overall it is a better than yesterday. I am sure there is still room for improvement.
- A condomaran goes upwind !