Light air performance of different multihulls?

[malbert73]

My opinion from racing and cruising is that DDW is fastest VMG without a spinnaker. And sailing angles (eg jibing downwind) is faster VMG downwind with a spinnaker.

Just clarifying as above folks aren’t clarifying which sails for DDW vs angles. Reason is that to sail a hotter angle with just main and jib/genoa requires 120-130 AWA which is too much extra distance to make it worth jibing. In those cases wing on wing is slowest through water but most efficient DDW VMG.

A dedicated spinnaker or assymetric chute comes alive with only a small amount of heading up from DDW. So then angles are better for DDW destination.

All of this from monohull experience so maybe different on cat.

[mikedefieslife]

On a cruising cat you will have to account for more leeway too the more you come off DDW.

Also there is a comfort issue. waves at 180 +- 10-15 degrees is much more comfortable than waves lifting up one stern quarter then the other whilst the opposite bow is on the downside of the wave.

[Dave_S]

Originally Posted by malbert73

My opinion from racing and cruising is that DDW is fastest VMG without a spinnaker. And sailing angles (eg jibing downwind) is faster VMG downwind with a spinnaker.

Just clarifying as above folks aren’t clarifying which sails for DDW vs angles. Reason is that to sail a hotter angle with just main and jib/genoa requires 120-130 AWA which is too much extra distance to make it worth jibing. In those cases wing on wing is slowest through water but most efficient DDW VMG.

A dedicated spinnaker or assymetric chute comes alive with only a small amount of heading up from DDW. So then angles are better for DDW destination.

All of this from monohull experience so maybe different on cat.

This is what I have seen as well and this includes some fast cruising cats who take racing fairly seriously. It would be different if your target is 20° off DDW.

[Tupaia]

Originally Posted by mikedefieslife

On a cruising cat you will have to account for more leeway too the more you come off DDW.

Any leeway off the wind will be in your favour.

Originally Posted by mikedefieslife

Also there is a comfort issue. waves at 180 +- 10-15 degrees is much more comfortable than waves lifting up one stern quarter then the other whilst the opposite bow is on the downside of the wave.

We are talking "light wind" conditions, there will be very little sea state.
DDW may give you a better VMG if the wind is stronger, the wave action you describe, or if the boat is slow, but it is not the case in light winds on a fast boat.

[malbert73]

Originally Posted by Tupaia

DDW may give you a better VMG if the wind is stronger, the wave action you describe, or if the boat is slow, but it is not the case in light winds on a fast boat.

What sails on what boat? My boat is quite fast in light wind and I have to head up way too high to make good VMG DDW to get the jib pulling. Spinnaker is a different story

[Tupaia]

Originally Posted by malbert73

What sails on what boat? My boat is quite fast in light wind and I have to head up way too high to make good VMG DDW to get the jib pulling. Spinnaker is a different story

Multihull thread... Most monos aren't going DDW at all in the winds being discussed.

[mglonnro]

“Being light is being green,” he says. “When you sail in the Med and you have a boat which is able to sail in 6-7 knots of wind, then you are only going to use your engine 5% of the time. “If your boat needs 10-12 knots of wind, then you’re going to be using your engine 60-65% of the time.”

Stumbled upon this quote. Marc van Peteghem interviewed:
https://www.yachtingworld.com/catama...terview-126258

[arsenelupiga]

Originally Posted by mglonnro

Stumbled upon this quote. Marc van Peteghem interviewed:
https://www.yachtingworld.com/catama...terview-126258

“Being light is being green” so true. didnt worry about it till this year when we hit weeks of light sub 10 kn winds. Luckily we are light enough to got away with mostly sailing. As per VPLP recommendations that means 3 T less than max load for our boat.

[wingssail]

Originally Posted by arsenelupiga

“Being light is being green” so true. didnt worry about it till this year when we hit weeks of light sub 10 kn winds. Luckily we are light enough to got away with mostly sailing. As per VPLP recommendations that means 3 T less than max load for our boat.

The other thing about being lighter is the fun of sailing it. Another of Marc van Peteghem's quotes from the same article, “In the 70s, people were sailing on simple boats. Over time, they got older and richer and wanted a bigger boat with more comfort – more, more, more – and we drift away from the pleasure of sailing."

This concept holds true for multihull and monohull boats, and let us not forget what got most of us into sailing in the first place: the fun of it.