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ddubois
03-04-2012, 04:51 AM
I'd like to hear the process some use for outside gybing an asymmetric when SH. Specifically how you maintain coordination of the turn with the clew of the A-sail around the front of the boat and doing the big in-haul of the new sheet while at the same time gybing the main. It doesn't seem the autopilot can be much help like it can be with a symmetric where you can set it deep, go jibe the pole then come back and make the turn and gybe the main.

Thanks,
Doug

Ragnar
03-04-2012, 08:58 AM
I think I've done this maybe 4 times because it's a PITA, but here is my self-taught process:

Sail down to 170 apparent - on autopilot the entire time.
Shift load from guy to tack line & bring sail to bow
Pole forward, down & on deck. Pole lift & downhaul stay attached but loose
Sheet out all the way to "flag" the Asym in front of the boat.
Push the + or -10 a few times on the autopilot to bring the bow over to 160 AWA on the new gybe
Gybe Main
Pull in new spin sheet
Pole up, near forestay
Pull in new guy while releasing tack line & bring pole back
Adjust course, guy & sheet as necessary


With 5 lines on the spinnaker, it's a mess. And to think we do this stuff voluntarily. At night. I guess that's why sprits were invented.

I suppose if you had a sock, it would somehow come into play.

BobJ
03-04-2012, 10:22 AM
"I guess that's why sprits were invented." Yep - here's how it works on my boat:

Like so much of what we do, success is mostly in the prep:

1) The currently-loaded sheet is sorted and ready to run out (this is the most important)

2) The spinnaker is full and drawing well (come up slightly if necessary)

3) There's enough sea room in case you have to gybe back (to clear a wrap) and gybe again

Then I use a two step gybe (kite first, then main):

4) Bear off to a deep broad reach so the spinnaker gets soft behind the main (on my boat it's usually two ten-degree bumps on the AP)

5) Immediately throw off the loaded sheet and make sure it runs out well

6) Haul like a sonofagun on the new sheet until the clew passes the headstay and is on its way back to the cockpit. I only do inside gybes, but outside gybes would be the same.

7) Stop and take a look - often I can ease the spinny sheet back out at this point and run wing-and-wing for extra VMG to the leeward mark (if needed)

8) Bear off another 20-30 degrees (two or three more bumps on the AP) and duck as the main comes across. On most sprit boats you have to gybe "all standing" or you'll immediately broach

9) Trim for the new course and clear your loaded sheet for the next gybe

In the "Elmer" department, the most common cluster is the old sheet getting hung up while pulling the kite around. I've also been known to get anxious and hit the wrong button on the AP - I nearly T-boned Moonshadow last year with that one. Also, if you do step (7) under the Gate you will discover that "Yes Virginia, sprit boats DO round down."

Summary: Prep, kite first, then main.

ddubois
03-04-2012, 04:54 PM
Thanks. So it sounds like the AP is part of the process. I was thinking of my Melges24 days where 'driving' the clew around the front of the boat was so critical. But it sounds like letting the AP hold it at 170 AWA is deep enough to get the clew around by hand but not so deep to throw the boat into an early gybe.
On a side note, I was reading a post about where to mount the AP control head. I think I'm convinced now to move it from the back of the cockpit to the bulkhead at the front of the cockpit which is where the spin sheets will be on the cabin top winches.

Doug

BobJ
03-04-2012, 08:47 PM
Yes, the AP makes it pretty easy but the control head needs to be right there. Also, I run the spin sheets on the primaries. The cabin top winches are in a better spot but are too slow.

The deep broad reach angle will be mostly boat-specific but also determined by sea state. If you are having trouble pulling the kite around, go slightly deeper. If the sea state is causing the main to start across prematurely, come up slightly.

If the main is slow to come across the vang is probably eased too much and you'll be rolling - you're headed for a broach on the new board. By the way, my vang's tail is split and led aft on both sides so I can reach it quickly.

Finally, it's really important not to oversteer through the second stage or you'll broach, just like with a live helmsman. The AP actually helps with this since it straightens you right out when the main comes across. Just don't go too far around and all will be well. This is also the reason for the pause in step 7 - you ease the kite back out so you're less likely to broach once the main comes across.

It doesn't matter how hard it's blowing - I'm a lot more comfortable gybing with the autopilot than with crew.