Cruising cat - sub 90 degrees tack upwind

[arsenelupiga]

pinching ideas for performance improvements on our L 400, borrowing from Excess. Interview with VPLP:

https://youtu.be/qdhhxLU--i8

It sheds light on why we were able to sail with so little leeway.

It is because hulls are shallow 2.5:1 according to Django and therefore keel is deeper. We draw 125cm measured. And this is significant for upwind according to VPLP.

I a hoping that small leeway will remain once i install upwind gennaker to boost upwind in light winds where monos still have upper hand.

[django37]

Some lowaspect ratio minikeels are more lowaspect than others,

[arsenelupiga]

Originally Posted by django37

Some lowaspect ratio minikeels are more lowaspect than others,

that is pretty dramatic difference. Explains overall perception of cruising cats - condomarans. Who in this world would think fat, made for charter, continuously motoring, superwindage Lagoons perform best upwind from keeled cats

Unbelievable !

[Uncle Bob]

Originally Posted by arsenelupiga

that is pretty dramatic difference. Explains overall perception of cruising cats - condomarans. Who in this world would think fat, made for charter, continuously motoring, superwindage Lagoons perform best upwind from keeled cats

Unbelievable !

Oh you are so right, UNBELIEVABLE.

[arsenelupiga]

Originally Posted by Uncle Bob

Oh you are so right, UNBELIEVABLE.

truth is not always easy to accept but congrats for trying. You will get there as further details come out.

[BigBeakie]

I would bet on a Grainger keeled cat against ANY Lagoon, anytime[emoji57]

[arsenelupiga]

Originally Posted by BigBeakie

I would bet on a Grainger keeled cat against ANY Lagoon, anytime[emoji57]

You are right, there are really fast keeled cats. My statement bit tooo heavy. Should add in its condo class.

But then again, to be fair comparision, 40 ft Grainger keeled cat loaded with goods 2.5T like us, forget about our extra space, would be less predictable.

[django37]

This is my Lagoon pre “Round the world”, no bimini, trying to go to windward with the works sails, which are blown completly out of shape in this 30 knots wind. So we have more than 110 dgr between tacks, and the boat is trying to exceed hullspeed making enormous waves. The solution is much better sails, that dont stretch, so you can point 40 dgr TWA, and sail a bit slower, between 7.5 and 8 knots. The Lagoon is my 7th cruising cat, and the first without daggerboards and the first I have not designed myself ...

[arsenelupiga]

Originally Posted by django37

This is my Lagoon pre “Round the world”, no bimini, trying to go to windward with the works sails, which are blown completly out of shape in this 30 knots wind. So we have more than 110 dgr between tacks, and the boat is trying to exceed hullspeed making enormous waves. The solution is much better sails, that dont stretch, so you can point 40 dgr TWA, and sail a bit slower, between 7.5 and 8 knots. The Lagoon is my 7th cruising cat, and the first without daggerboards and the first I have not designed myself ...

great test ! I have been only up to 25 kn or so apparent with full sail and in my end of world strong winds mean lots of waves or squally so configuration i would consider less usable as i am usually deeply reefed.

Question for you if you do not mind- from your experience :
Would you choose non-stretching working sails or upwind gennaker to improve lightwind upwind performance and reaching, considering new gennaker is due shortly and I replaced my sails 10k nm ago with standard L 400 sails from incidences ?

[django37]

Originally Posted by BigBeakie

I would bet on a Grainger keeled cat against ANY Lagoon, anytime[emoji57]

Yes, certainly, they all have good sails and are only half the displacement. But put the average charter person at the helm, and equip the Lagoon with good sails and a competent helmsman, and it might be different!

[django37]

Originally Posted by arsenelupiga

Question for you if you do not mind- from your experience :
Would you choose non-stretching working sails or upwind gennaker to improve lightwind upwind performance and reaching, considering new gennaker is due shortly and I replaced my sails 10k nm ago with standard L 400 sails from incidences ?

I am considering a longer prodder and a sort of screecher in low stretch cloth, that will sheet aft on the nomal genoatracks. I dont dare to hoist it on the masthead spi halliard, so it will be on the gennaker halliard just above the hounds. And it will have to be nearly furled at each tack. Have a gennaker for beam reaching.

[fxykty]

Originally Posted by django37

I am considering a longer prodder and a sort of screecher in low stretch cloth, that will sheet aft on the nomal genoatracks. I dont dare to hoist it on the masthead spi halliard, so it will be on the gennaker halliard just above the hounds. And it will have to be nearly furled at each tack. Have a gennaker for beam reaching.

One thing to be careful about a screecher or even a gennaker on a longer prodder is excessive lee helm. Racing cats (and tris) with very long prodders usually have masts set far back for that reason.

For windward work placing the tack further forward and using the genoa tracks will mean the sail angle will be even tighter than with the genoa. So cut the screecher shorter on the foot and sheet as far forward as possible. I assume it will fit inside your shrouds?

[44'cruisingcat]

Originally Posted by arsenelupiga

that is pretty dramatic difference. Explains overall perception of cruising cats - condomarans. Who in this world would think fat, made for charter, continuously motoring, superwindage Lagoons perform best upwind from keeled cats

Dunno. Would anyone?

[arsenelupiga]

Originally Posted by 44'cruisingcat

Dunno. Would anyone?

my aim is to do 3.5 - 4 kn VMG direct against wind in 10 kn true in flat water loaded with all goodies for transocean sailing.

So, help me get there with some constructive ideas.

I will go what Django said, ie screecher from prodder to jib leads. This gives me larger jib around 48m2. This compares to my current jib 35m2.

Currently we can do 3 kn VMG direct upwind in 10 kn true. How much would that extra carbon sail improve ability is the question.

To extend prodder, not sure of the impact as per fxykty... Excess cats that have longer prodder have mast further back so that is in line with fxykty point.

[44'cruisingcat]

More sail area is likely to produce more speed. This will have the effect of widening the gap between AWA and TWA. You may not be doing 90' tacks any more. However your VMG could improve.