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pbryant
04-15-2016, 11:39 AM
After having my main rudder completely refurbished at Svdenden's (at considerable cost) I'm considering using a drogue chute as an emergency rudder. There is a good demonstration posted here: http://bermudarace.com/emergency-steering-drogue-new-approach/. Granted, potentially steering over 1,000 miles with any manual method would be a real hardship, but it's do-able.

Steering in port is easily accomplished with my outboard engine because it swivels in the engine port. (Which, by the way, also provides some steerage even when shut down.) I practice this nearly every time I dock, since steering with the engine allows me to approach the dock at speeds below steerage speed (and also when backing away from the dock, since Alberg-designed boats like mine have practically no directional control when motoring slowly astern).

What will the inspectors say?

sleddog
04-15-2016, 12:41 PM
You might check out Forum thread "Drogue as Emergency Rudder," begun 11/21/2014.

pbryant
04-15-2016, 01:42 PM
You might check out Forum thread "Drogue as Emergency Rudder," begun 11/21/2014.

Thanks for the reference. The specific case that is sited in that post was C&C 30 UNCONTROLLABLE URGE that lost its rudder off San Clemente island. I've read the full report. The crew was attempting to escape running aground by motoring away directly upwind from the island, which was alee. They tried everything EXCEPT dousing the Jib, centering the main, hauling it in tight, and using the main as an air rudder. As long as there's a reasonable amount of wind, any boat can be induced to motor upwind by that method. I had to do that once off Stockholm, Sweden in heavy seas, when I lost the delicate spade rudder by being taken aback by a swell. I had to motor 100 miles upwind, and it worked better than an autopilot. The traveler provided about 20 degrees directional control port/starboard.

Most of the jury-rig emergency rudders I've seen don't look like they'd last the 1,000 mile worst-case journey. And whatever broke the main rudder is likely to take out the emergency rudder as well. I have heard of very few failures of rudders hung from full keels. The primary benefit of this rudder configuration is the strength and protection provided to the rudder. It is hinged at top and bottom, well distributing the forces on the rudder. My selection criteria is: an emergency rudder has to be stronger than my keel hung rudder, and I haven't found one yet, regardless of price. It'd better turn a battleship or it's unsuitable. I am not going to back up a strong rudder with a weak rudder. That just doesn't make any sense. A drogue rudder might not work well in heavy following seas, but there's not much to break.

Those with spade rudders have more options since, practically everything is stronger than a spade rudder. Only the rudder post is supporting a spade rudder. Inadvertently backing up in heavy seas is enough to take one out (as I learned the hard way).

I'm not in a position to break out another $3,000 for a commercial emergency rudder, and there's hardly any room on my little boat's stern to mount one. Maybe I'll slap a couple of plates on my swiveling outboard engine, and use that as "Plan C".

sleddog
04-15-2016, 02:24 PM
It'd better turn a battleship or it's unsuitable.

There was a good discussion a while back on battleship rudders and how the BISMARCK was sunk due to a jammed rudder:).. 5/11/2015

A keel hung rudder is certainly more protected than a spade. A concern would be how long the rudder shaft had been immersed, and if elderly, the possibility of internal moisture in the blade. Welded internal structure can turn to rust over time when submerged.

Not sure an inspector would want to make the decision what is suitable for emergency steering. It's your choice. A drogue might be fine. Especially if tested in "at sea" conditions with the main rudder tied off. A drogue certainly meets two criteria: simple and strong.

However, the drag of a drogue may well be sufficient that if you have a family waiting at the other end, things might get worrisome due to slow progress.

Plan C sounds workable as a backup to Plan B. That, and twin jibs, would get the vessel downwind lickety split.

pbryant
04-15-2016, 02:36 PM
> There was a good discussion a while back on battleship rudders and how the BISMARCK was sunk due to a jammed rudder.

Hopefully, I won't have any British biplanes dropping bombs on my rudder. :o

My rudder shaft is brand new and shiny! Svedsen's put a lot of work (and my money) into it. You're right about that concept of dragging a drogue 1,000 miles to Hawaii. I'd like to be at my grandkids' graduation from college. But I'll be flying twins, so dead downwind won't require the drogue - unless my modified full keel falls off (and it's not a bolted on type), I'll still have good lateral (yaw) stability.

sleddog
04-15-2016, 04:33 PM
For those who have not yet discovered it, John Letcher's Self Steering for Sailing Craft is available to be downloaded and read without purchasing this classic book, the best on the subject, with relevancy to emergency steering.
http://www.jesterinfo.org/selfsteeringforsailingcraft.html