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PostPosted: Wed Apr 17, 2013 1:46 pm 
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I know this has been mentioned a few times but I couldn't find any responses besides "yah it sucks".

I have done many ocean surf landings and launches and always get a lump in my throat on days where the surf is 2' or more. With the rudder and drive up, my Revo 13 wants to turn sharply to the left. I end up doing large sweeping strokes on the left side only but it's not fun and I've flipped a few times when I couldn't correct in time, the boat just WANTS to be parallel.

Does everyone's Revo handle like a dingy without the rudder? Any tips? I've been thinking in the future I'll unclip but leave the rudder down, take the chance of some breakage.

Jim


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PostPosted: Wed Apr 17, 2013 1:52 pm 
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Location: Takoma Park, MD
yah... it sucks :)

Mirage yaks will perform illegal u-turns readily when the rudder is up. You need to raise the rudder at the last possible moment.

But even if your rudder hits bottom, the cord is flexible enough to allow a little play, so it shouldn't break anything... just make sure your shock cord is not cleated when you land.

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2011 Oasis - Lunalilo Express
2012 Revo 11 - Lunalilo


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PostPosted: Wed Apr 17, 2013 3:17 pm 
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Same thing happens with my Revo11 and I surf launch all the time.
The good news is the Revolution models perform quite well in terms of cutting through the breaking surf compared to the wider ones like the Outback and the Sport (which I used to have).
But yeah, paddling a Revo without the rudder down is a frustrating as hell :evil: There's really not much of a tip one can give except wait for the waves, time it right, jump in and keep the bow pointed into the waves while you paddle as hard as possible. Once you get some forward motion, drop the rudder ASAP. Paddle plus rudder is actually not bad at all. Mirage drive can always be dropped in after the first few breakers.


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PostPosted: Wed Apr 17, 2013 3:23 pm 
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and tie down everything you dont want to lose!
S#|T happens, even when you think you're well prepared, so leash your gear!


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PostPosted: Wed Apr 17, 2013 3:27 pm 
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Joined: Sun Aug 12, 2007 5:17 pm
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Location: Auckland NZ
I have never been on a Revo (my boat is an Adventure) but landing through surf presents a problem on all kayaks in my experience.

I spent considerable time reading up on how boats are rolled by breaking waves and in reading research from the development of the Johnson series drogue (a device for preventing breaking wave capsizes at sea). The problem occurs when the boat is pushed from behind by a greater force (in the form of a wave) than can be overcome by the rudder - then the boat will have a tendency to turn in one direction or the other and, as it turns, the turning moment increases, making the turn impossible to recover, until the boat lies parallel to the waves, whereupon the breaking crest of the wave hitting the side of the boat rolls it.

In short steep waves there is an additional tendency for the bow of the boat to dig into the back of the wave in front which acts like a pivot point around which to turn the boat.

The most exciting, but on a kayak or a yacht, uncontrollable and potentially dangerous, situations are when the wave throws the boat forwards so quickly that it exceeds hull speed and starts to plane or surf.

The Johnson series drogue deployed from the stern acts as a drag, thus slowing the boat down, preventing it being lifted forwards and holding the boat, by the stern, pointing into and therefore perpendicular to the wave thereby overcoming the tendency to turn. What happens (and it is a beautiful thing to experience!) is that as the moving water of the wave catches up with the boat and tries to lift it forwards, the drogue catches the water behind the wave, slowing the boat down and in effect pulling it by the stern backwards through the wave. Because the drogue allows some forwards movement the boat and the wave move forwards together initially before the wave passes the boat as the drag kicks in - this has the effect of markedly reducing the impact of the wave on the boat and its occupants because both are travelling in the same direction, just at slightly different speeds.

The techniques I now employ are:
1. In small waves (up to ~2 foot face): prepare the boat outside the surf zone (rudder up, mirage drive & sail stowed, everything clipped on); wait for a lull in the sets; paddle in on the back of each wave and, as the next wave catches up, slow the boat down so that the wave passes under (around and over) you and your boat. Techniques for slowing include reverse paddling and putting both legs over the sides of the boat to create drag - this has proven to be enough in smallish waves. It is also possible to land through small waves under sail with the wind dead astern - the pull of the sail at the front of the boat tends to counteract the push of passing waves turning the boat from the stern but you will probably still need to slow the boat down using your legs.
2. In larger waves - I guess I have done 2-5 foot faces: preferably avoid landings in these conditions :idea: but if you do end up having to land on surf beaches where stand-up surfers are doing their thing, a scaled down series drogue will allow you to get back in through the surf without too much risk of being unshipped - you just throw the drogue out and pedal in against its drag until you arrive in knee-deep water when you get out of the boat & recover the drogue. In fact with my drogue deployed I have sat in the surf zone with surfers on their breaking waves whizzing past me for several minutes at a time just to get a feel for what happens. Under these circumstances I have ended up falling out of my boat - more due to my lack of balance than by the boat being turned over (the bucking is quite disconcerting) - but did not have a problem climbing back on board in the troughs.

Hope this helps and provides some food for thought.


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PostPosted: Wed Apr 17, 2013 3:32 pm 
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Location: Takoma Park, MD
Very interesting, thanks for the info. Do you think a drag anchor could act as a drogue?

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2011 Oasis - Lunalilo Express
2012 Revo 11 - Lunalilo


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PostPosted: Wed Apr 17, 2013 3:53 pm 
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wow stobbo, good writeup on the "landing" part of the OP's question.
I also employ the "throw both legs over the side" method to slow myself down and balance the yak as I paddle in (Mirage drive stowed away at this point).

I've never had to land in anything more than 2ft though, I'm lucky in that my preferred beach launch is close to an inlet, so if the waves/weather are too rough for the landing I go back home through the inlet and land on the mangrove side (thank goodness for South Florida's intercoastal waterways).


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PostPosted: Wed Apr 17, 2013 5:28 pm 
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Jcan, I'm in SE Florida as well, usually launch out of Dania. Your name sounds familiar, we may have crossed paths. Good idea taking the inlet, as long as you don't get run over by all the boat traffic!

Stobo, the series drogue is very interesting, never heard of it even with 6 years in the Navy. It sounds like a last-resort high skill type of item to me but I'm going to look into it.

For now I think I'm going to put the larger sail rudder on my Revo and leave it down/unclipped as Jcan suggested. This should minimize the constant fiddling with the steering and keep her straight on the way in/out. I love the Hobies in that I can jig all day and not have to paddle back but wish it had a little better keel.

Thanks everyone for some good inputs!


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PostPosted: Thu Apr 18, 2013 7:01 am 
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Thunder, send me a PM if you want to link up to go out from Dania anytime.
Also, I did the big rudder upgrade, trust me its worth it!


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PostPosted: Sat Apr 20, 2013 8:30 am 
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Joined: Wed Sep 02, 2009 1:14 pm
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Location: Moab, Utah
Stobbo, I am very interested in your series drogue. I have heard of them before, but have never found any details on construction and use for a kayak. Can you share any details, e.g., did you build it yourself or buy one? length of drogue and length of line you use to atttach it? number and diameter of cones? what are the cones made of? source for a manufactured version?

Have you ever tried using the drogue in large following seas on the open ocean to prevent a broach? or tried attaching it to the bow of your kayak while beaching through surf paddling backward (to allow you a better view of incoming waves)?

Thanks for your thoughts and suggestions.


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