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John Hayward
09-23-2007, 03:12 PM
Hi All,

There is a thread on Emergency Rudders on the Techniques section, but my question is a little different. I have a monitor self steering vane and I was thinking I might get the Mrud system. The people at Scanmar tell me it's approved as an emergency rudder for sanctioned ocean races and thoroughly tested but I want to make sure before I spend $1000 it will satisfy the SSS emergency rudder requirements????

Also: Are there any easy, inexpensive, generally accepted ways to meet the emergency rudder requirement? There is a discussion on the other emergency rudder thread about foam model aircraft wings and carved 2X10's being made into emergency rudders. Will these have to be tested to meet the "demonstrated" portion of the emergency rudder requirement or are they following some generally acceptable guidelines so testing and demonstration is not necessary?

I have a Valiant 40, it is built like a tank not a racer and an emergency rudder is one of the few requirements for the race that I doubt I would have were it not required. If I can carve a 2X10 into the shape of a rudder, attach it to the supports for the Monitor or in some other acceptable fashion, meet the requirements for the race and be out $40 not $1000 I would probably go this route. At this point I am only concerned about something that will meet the minimum requirements of the SSS be acceptable to whomever inspects my boat before the transpac but I will spend the $1000 if I must.

I would appreciate any help here, especially from people that might be inspecting and evaluating my emergency rudder system.

Thanks in advance,
John

Alchera
09-23-2007, 04:52 PM
I have the Monitor MRUD on my J120 (40') and it has met the SSS requirement in the three previous races with that boat. Furthermore, I've never been asked to demonstrate it's operation since it is a commercially available product designed for that purpose and tested by the company.

Although it is also possible to use the standard Monitor paddle as a means of (slowly) steering the boat, this doesn't work very well in any kind of a sea and I was not allowed to claim this as an emergency rudder on my Ericson 38 for the '96 SSS TransPac. So I ended up doing what you are thinking, building a rudder that could be lashed to the Monitor frame. I was never really happy with the way it worked, and I'm glad I never had to use it.

If you have any kind of a homemade emergency rudder solution, be prepared for the SSS inspector to ask you to mount it in it's operational position. Then if there is any doubt in the inspector's mind about whether it is strong enough or will steer the boat effectively, you may be asked to demonstrate it under sail.

- Mark

tiger beetle
09-24-2007, 06:18 PM
The EMRUD has been accepted in the past as an alternative steering system (emergency rudder). That said, you need to determine whether or not it will steer your Valiant 40, and how well it will do this. ScanMar may have some thoughts on how it ought to operate, but you still need to verify it for yourself.

To meet the minimum requirements for the TransPac you will need a rudder that will allow you to sail the boat under control - meaning tack, gybe, go upwind and downwind. If the rudder is marginal than you may be doing this at less than full sail area - but the rudder needs to allow you (as skipper) to control your boat.

As a past TransPac inspector, I asked for the yacht to have it's emergency rudder installed (ideally before I arrive). As Mark/Alchera pointed out, if the inspector is suspicious of how well it will work, well, we get to go sailing on the bay for a couple of hours and try it out.

If you want to build something simple out of a 2x10 for your 22,500 pound 40 foot boat, by all means do so - then go try it out. By the time the inspector visits the boat you will know how well (or not) the emergency rudder works. A 10" chord is rather small for a boat your size, may stall easily, and may need to be quite deep to have sufficient control over the boat. If the home-built rudder doesn't work out to your satisfaction, then you can still head over to ScanMar and purchase the EMRUD - but you had better go try it out before the inspector shows up...

- rob/tiger beetle

AlanH
09-26-2007, 11:06 AM
My J-24-sized 2 x 10 emergency rudder is intended to steer a Santa Cruz 27. It actually managed to steer my Santana3030 OK in 15 knots of breeze, if I tucked in a reef. I have no doubt that it will handle the Santa Cruz just fine, since it's easily 3/4 the chord and depth (though it doesn't go as far down in the water) as the stock rudder.

I must say that I'd have significant reservations about using it on a Valiant 40!

I strongly, *strongly* recommend going to the emergency steering seminar that the SSS will put on, and seeing what some of the larger boats have for their systems.

Another thing to keep in mind is that one of the likely scenarios that would cause an emergency rudder to be needed, is smacking into something and bending the rudder/rudder post and jamming the whole thing off to one side. This, of course, will steer the boat in circles and you will go nowhere. So I always spend some time thinking about how I might get rid of the rudder if I had to. I carry a piece of 2 x 4 long enough, and cut to the right dimensions so that I can ram it down the rudder tube and shove the rudder and rudder post out..

Also, it's important to think on how you'll set up a self-steering system with your emergency rudder. For me, I will lash a 2 x 4 to the stern pulpit, with the piece of wood lying on deck, just forward of the lazarette hatch. The wood is drilled in the correct location so that an autohelm tiller pilot goes in the right place, and I'm on my way....

AlanH
09-26-2007, 11:10 AM
One nice thing about the EMRUD is that you can attach a $400 autohelm 1000 to the top of the Monitor (figure out exactly where to mount it) and control the boat with that. You won't surf like a wild thing I'll bet, but it should work.

John Hayward
09-29-2007, 03:23 PM
Rob and Alan,
Thanks for the information. I was not actually thinking of a 2X10 for a boat as heavy as mine, but was hoping there was some simple, practical, inexpensive solution that was acceptable to SSS as an emergency rudder so I wouldn't have to spend $1000 for the Mrud system. This is definitely *not* how I normally approach maintenance issues on my boat, but since many Valiants have been sailed around the world and there has not been one instance of the skeg hung rudder failing that I am aware of, I would not invest in the Mrud system or worry about an emergency rudder at all were it not a requirement for the race. Hence my hoping for a more inexpensive solution.

Since there does not appear to be any "generally acceptable" inexpensive solution and I don't want to try to engineer a solution from scratch and hope the inspector will find it acceptable, I guess I am stuck with the $1000 solution. Guess I will just have to look at it as part of the entry fee.

Alan, I do hope there is a seminar on Emergency Rudders and I will surely attend. I am not going to do anything right away, but want to have this issue dealt with and approved well before the race. I don't want to wait till the last minute, do something unacceptable and not be able to participate. Most of the required equipment I already have on the boat, I have already done a qualifying cruise and just have some minor things like replacing the standing and running rigging and, perhaps, the mainsail and I'm ready!

John/Dream Chaser
Valiant 40 Performance cruiser/tank

haulback
09-29-2007, 07:07 PM
A question that could be addressed in your case might be...

For a directionally stable design (compared to fin/spade rudder combo) such as yours, would the ability to steer the vessel by sail configuration and trim be considered by the RC???

I have herded my boat along on various points of sail with the tiller lashed amidships. I may not be racing by that point, and I would not be up to any fancy manoeuvres, but I do not feel daunted by the issue.

Lets face it, my boat has a fully attached 'barn door' rudder - am unsure whether your rudder is fully attached or not. If I were to lose it, quite frankly, at that point steering would become the least of my problems....because more than likely the whole back end of the boat would be torn off.

Of course, if you lose your wheel steering, it is assumed you have a workable emergency tiller to hook up to the top end of the rudder stock someplace.

Jim/Haulback

AlanH
09-29-2007, 07:23 PM
If you have an engineering bent and don't mind some math, take a look at Paul Kamens 2004 seminar for the Pacific Cup, on emergency rudders.

http://www.well.com/user/pk/PCrudder-04.htm

I have my doubts about the sailcloth one, however!

Rob MacFarlanes great article on emergency rudders from 2004 can be viewed here:

http://www.bluemoment.com/emergencyrudders.html


And then there's Kame Richards little photo journal here:

http://pineapplesails.com/articles/e_rudder/index.htm

Hope those are helpful!

haulback
09-29-2007, 08:29 PM
Should also mention that I have a Fleming windvane and purchased their back-up steering option when I signed-up for the '02 SHTP

But previously mentioned 'steering with the sails' test was done without it's assistance. Using it things become even better.

Point behind that particular exercise was to see how well I could get the boat to steer should windvane fall off the back of the boat and AP be non- functional.

Jim/Haulback

John Hayward
10-01-2007, 08:36 AM
Jim and Alan,

Alan, WOW, thanks for the links. Great information. I had thought about attending the PacCup seminars at one point but had forgotten about it. I might have to reconsider that too.

Jim, thanks for the information and ideas. I too can steer my boat with the sails pretty much anywhere but DDW but I'm pretty sure for insurance reasons if nothing else, I still have to have and emergency rudder. And, yes, if my rudder is "gone" I will probably be manning the emergency liferaft. If both the skeg and rudder are gone or severely damaged there will probably be an accompanying hole in the hull that will overcome my ability to bail..... I do also have an emergency tiller in the event that the wheel steering fails but the rudder and post are still intact.

Thanks again,
John