Mirage-Drive Storage on the Water ?

After a couple days of decent wind, I am thinking my pattern of Mirage Drive usage will be using it when going a substantial distance upwind, then removing it for the down-winder back to the beach.

So far, I have been stowing the Mirage Drive in the bow hatch when not using it.

But swapping it in/out while on the water seems attractive; yet opening the bow hatch on the water does not seem like that great an idea.

Just laying the Mirage Drive in the cockpit (leashed, of course) seems to work well enough when everything is going OK....although it seems like things could get messy if/when stuff happens....

Has anybody come up with something better ?

_________________
2015 AI in "Dune" - "The Grey Pig"
2017 Trailex 450 Trailer
Pre-September 2015 cradles
(anybody want to buy a slightly-used AI SpinKit?)
eMail: [email protected]

Pete, I leash it and leave it in the cock pit most of the time. If I am pretty sure I won't need it at all' I leash it and stick it out of the way under the bungees in the rear cargo area.

The guys with Hakas have it made as they just stick it between the slats of wood.

I tend not to use the front hatch except for emergency gear. I find it hard to get into once on the water.

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Greg

2016 AI - Spinn & Jib

“Out of sight of land the sailor feels safe. It is the beach that worries him.”
– Charles G. Davis

Do you bother swapping in the plug ?

_________________
2015 AI in "Dune" - "The Grey Pig"
2017 Trailex 450 Trailer
Pre-September 2015 cradles
(anybody want to buy a slightly-used AI SpinKit?)
eMail: [email protected]

Yes I put in the plug. Problem is I don't have a leash for the plug. This could be why I haven't seen the plug for a while.

_________________
Greg

2016 AI - Spinn & Jib

“Out of sight of land the sailor feels safe. It is the beach that worries him.”
– Charles G. Davis

If you put the drive in the rear well and put a bungee over it, leashing it is a very good idea. This is because the mainsheet and sail are MUCH stronger than the bungee. Learning this cost me about $500. SPLASH!

If you try to sail with an empty hole instead of putting in the plug, you'll get an impressive amount of water in your lap and will increase drag of the hull quite a bit.

But enough from my file of things I know but should not.

I have sailed my boat alongside my wife, her with the drive in and me with the plug in. She was faster (dammit!)

I think maybe the red boats are just faster.

Light or moderate air and she was pedaling, right?

_________________
2015 AI in "Dune" - "The Grey Pig"
2017 Trailex 450 Trailer
Pre-September 2015 cradles
(anybody want to buy a slightly-used AI SpinKit?)
eMail: [email protected]

Moderate breeze, reaching angle, and no, she was not pedaling.

It seems like the added drag of her fins vs my plug should have made my boat faster but it did not.

I'm sure she just had her sail trimmed a bit better but I like the hull color explanation better.

I was out solo yesterday in 10 - 12 kt winds in our TI. I typically bungee the unused drive but I was wondering if it wouldn't be better to somehow lock the pedals together in the middle and thus provide an extra dagger.

I have tested that idea too and found it doesn't work.

I suspect it's because the blades flex and align themselves with the water flow. A daggerboard is supposed to resist that flow and create an angle of attack by not being aligned with it.

If you're not going to remove the drive and put in the plug to get any (undetectable by me) advantage you can that way, the next best I have found is to put one pedal forward and keep the blades against the hull. I guess they create less drag when in the turbulence of the hull than when sticking down into undisturbed water.

Whatever the reason, it just seems to work better, boat seems to go faster.

If you take your feet off the pedals, one pedal tends to go forward. My interpretation: it's tending toward the position of least energy, least resistance.

Someone more careful than I am should go do some real, repeated (and repeatable) tests to find out what, if any, difference it makes what is done with an inactive Mirage Drive. Until that happens, I just have what I think I have observed.

I only have one day of real wind (average 20, gusting to 25) under my belt, but on that day it was pretty obvious that removing the Mirage Drive enhanced the boat's performance significantly.

The optimal use seemed to be Mirage Drive to pinch upwind and then the plug to reach back-and-forth on the downwinder back to the beach.

I am guessing there is a cutoff point: below a certain wind speed, no diff; above, a diff..... or maybe it's hull speed...

FusionEng probably has a number.

_________________
2015 AI in "Dune" - "The Grey Pig"
2017 Trailex 450 Trailer
Pre-September 2015 cradles
(anybody want to buy a slightly-used AI SpinKit?)
eMail: [email protected]