Drag coeffecient of Jellyfish?

[T34C]

I have sailed/raced in areas where jellyfish are very prolific in the summer months. I can't help but think these jellyfish in the water must increase the drag on the boat as you go through them. The question is this: Could you gain speed and advantage in a race by avoiding some of the clumps of jellyfish in the water much the same way that you play the wind shifts? Does anyone already have data compiled on this subject? If not, any ideas on how to measure this phenomenon?

Any thoughts on this would be great. I'm trying to really tune up my racing for next season.

[sailingdog]

Umm... exactly how would you predict where the clumps of jellyfish were... and of course, the amount of drag they present is dependent on what species they are.

[T34C]

Minor issues to be resolved...

Perhaps a scout boat on the course before the race???

[ReverendMike]

Are you applying for an 'Ignoranus'? Hmmmmm?

[Giulietta]

Actually its pretty serious if you ask my son Fred.

During the Nationals Qualifications, he lost a race, and I asked what had happened. He said that him a few others had struck a whole bunch of Jellyfish.

For a while I was laughing at it, then, a few others confirmed the same problem. They actually slow the Optimists down when you hit them with the dager board and with the rudder.

Fred actually told me he had to raise his dagger board several times during that one race.

He said he could not see them, but he could feel them as he hit them.

So in all this there is some truth....if you can trust the kid, that is...I do.

[Idiens]

Was that those Portuguese Man-o-Wars? Nasty!

[ReverendMike]

I withdraw the accusation, sorry T.
M

(though I'm skeptical of any effect on a keelboat of any size)

[T34C]

Originally Posted by ReverendMike

I withdraw the accusation, sorry T.
M

(though I'm skeptical of any effect on a keelboat of any size)

Apology accepted.

I have sailed in areas where the jellyfish in the water were pretty dense. I think they wold certainly be dense enough to see from the deck. Since sailboat racing is a game of inches, I think steering around them or tacking away from a known area might help. It would be helpful to know how much they slow you down to help with the decision making process of when to tack away.

I think this idea might have played a part in the AC last summer. If they had spent a little more time looking at (into) the water instead of trying to second guess the wind... who knows??? The Mug could have been moved back to NZ.

[Libellula]

I must wade in
I have raced for 35 years and can tell you that short of catching a crab pot or sailing into a hole
Strategic errors lose more races than anything else. I would venture to guess that if attention was paid to the relative position of boats in a race and the relevance of these associated positions analyzed correctly, that a gaggle of jellyfish would not affect the results
So I guess if you have everything else right- then you can worry about jellyfish

[T34C]

Originally Posted by Libellula

I must wade in
I have raced for 35 years and can tell you that short of catching a crab pot or sailing into a hole
Strategic errors lose more races than anything else. I would venture to guess that if attention was paid to the relative position of boats in a race and the relevance of these associated positions analyzed correctly, that a gaggle of jellyfish would not affect the results
So I guess if you have everything else right- then you can worry about jellyfish

But, you have not measured this "jf affect"????? Hmmmmm???? So we don't really know how much of an adverse affect they have on your boat. Perhaps when you thought your tactics were better it was really that the other boat was being slowed by the jf affect.