1
That guy has balls...literally!
Bob23
Beats the Mastendr...!
J.
Nice video.
What I want to know is how did the skipper 'adjust' his rail down attitude.
His ketch started out so so, then rail under, then rail up.
The weighted sea bags always seamed to be on the same length tether.
and hung from the same location. Beats me.
I saw this concept but with butts hanging over the side of a much smaller
sail boat in The Ensign magazine.
And of course there is the 'get her off the bottom' concept, but working
with the keel end.
skip.
Shawn:
He has a line to each bag that allows him to pull them in or out to adjust the angle
How does he PULL IT OUT?
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It's difficult to see, but it looks like he does let out the tether (halyard?) as he goes, then pulls them in once clear of the bridge to bring the weight back over the boat.
I would have been concerned about breaking the mast. I'm not an engineer, but it would seem to me that putting that much weight directly at the top of the mast would stress the rig considerably more than distributing the stress over the length of the mast (like when the stress is coming from a sail).
He has a line to each bag that allows him to pull them in or out to adjust the angle.
Shawn
""I would have been concerned about breaking the mast."
That was what I was thinking was going to happen too. The notes say it was 4000 pounds of water. Hope his standing rigging is up to that.
Shawn
That guy does not have balls he is nuts.....talk about more money than good sense......Phil
Heck I would not worry about the mast breaking. Heck lines have been tied to the top-O-mast for centuries to pull hulls over at low tide and scrape away the barnacles. The sail it self pulls the hull over every time the boat heels.
skip.
skip , if that guy mis-cal. , he will tear the mast off the boat, that is one good looking boat to have a bridge wearing your mast....Phil
I think that's actually a great idea. There's really no risk of the rigging failing from the wieght of the balls. Using his ship's inclinometer to get the angle of heel and knowing mast's vertical bridge clearance he can easly calculate his height when heeled using basic trigonometry. Since he uses water to weight the balls, no need to store that ballast aboard. It's a simple solution to a major problem for a boat that large.
I suppose things would get interesting if he were to try this with any traffic around.
I don't think my balls will ever be big enough to heel over even my little Com-Pac this way ;)
--Greg
Considering the loads... The mast would be under compression and the video proves it is up to that load. I'd also worry about the coach roof/compression post/bulkheads under the tabernacle. If anything in there was soft you'd think something bad could happen. The outside shrouds would be under tension, looks like 4,000 lbs of tension, right? No clue what the diameter of his shrouds are but they were also obviously up to the load. That load would also be on the outside chain plate/bulkhead. You would really have to trust the construction there, or again bad things could happen. Obviously this guy trusts his shrouds and chain plates. Pretty cool to watch but I'm not going to lie, I'd be reluctant to try it myself...
Quote from: NateD on November 15, 2009, 02:17:09 PM
It's difficult to see, but it looks like he does let out the tether (halyard?) as he goes, then pulls them in once clear of the bridge to bring the weight back over the boat.
I would have been concerned about breaking the mast. I'm not an engineer, but it would seem to me that putting that much weight directly at the top of the mast would stress the rig considerably more than distributing the stress over the length of the mast (like when the stress is coming from a sail).
This was too big to not be in the Internet... If you trust the Internet, it appears that the boat is an Alden 58-60 Yawl-Cutter. The bags are 1 ton each. The skipper's name is David and he is from New Zealand, and he has deviced this contraption to be able to sail the ICW...
I bet that you won't see Aratinga aground either, at least not for long... I thought that in New Zealand they only had sheep jumping over fences but it looks that they may also have boats going under bridges big time!
J.
The following is from the newsgroup, rec.boats.cruising:
--------------------------------------------------------------------------------------------------------------------
Late last night, a huge sailboat came ghosting into this marina.
David, her owner and captain usually sails Aratinga, a 60 foot Alden
with an 80 foot mast, outside on the open ocean but he said he thought
this year he?d like to try the ICW. Now? this is quite the
accomplishment, given that the fixed bridge heights on the ICW are all
around 65 feet. David ingeniously rigged up a way of tilting his boat
over so that she ?slides? under the bridges, healed up on an angle. He
has two one-ton (yes, 1 ton) thick rubber bags of water hanging midway
up his mast. His boat has a slight tilt to starboard anyways and when
he wants to tilt Aratinga over to pass under a bridge, he lets the
line out on these bags of water so they hang over the side and that
increases his starboard list. He figures that to cut 10-15 feet off
his mast, he has to let the bags hang out 10-15 feet to starboard.
It?s worked up to this point and I?ll bet this New Zealander will be
the talk of the ICW for years to come.
And what do you think for this other technique for going under a bridge...
http://web.archive.org/web/20080504230717/http://koti.mbnet.fi/~soldier/towboat.htm
J.
David - Thank you for the nice concepts. Frankly, I'd rather be.. you know. But being temporarily deprived, surfing the web and participating in fora like this one can be a nice and rewarding alternative. Capt. Jimmy Wilkerson of the towboat CAHABA was very lucky. As explained in the article linked to the pictures, the real lucky factor may have been that the tugboat had a central fuel tank which had just been filled up and which acted as ballast permitting enough momentum to right the boat up before she would flood. Releasing the barges was a "standard" manoeuvre to clear the bends in the river. Which was also a good thing because had the barges not been released the outcome would not have been much different than that of the freighter in the Welland Canal posted by Skip...
J.
As far as the stress on the mast - it is quite different than that imposed by the sails. These weights are placing a downward force on the rig, as compared to a sideways force applied by sails creating horizontal lift. Yes the primary force is compression. The weight being suspended from the top of the mast would introduce an out of column condition except that the lower shrouds are there to prevent that. Raising or lowering the weights wouldn't change leverage, but he was using control lines to swing the bags in or out for more or less leverage. This process is the the same as is used to get grounded boats off the bottom - simply tow a boat sideways by it's halyard (gently of course). I have heard tales of booming out water ballast to the same effect. I'm sure one of those fancy schmancy canting keel ocean racers could do this trick quite handily.
The real tragedy here is that sailing vessels were here doing humankind's work long before automobiles and should be accorded seniority. Maybe all bridges should be replaced by tunnels, because as the global warming brings higher water levels the bridge problem grows ever more acute. Not only that, but boat builders have come and gone but never asked for a tax payer bail out. I guess your achievements are only as good as today - no respect. My hat's off to Kevin Costner - three cheers to water world. But even there the dogma of the smokers is persistent - must be a human thing. Is it possible that one day we will have 5W/20W filling our veins? I'll bet some petro-chemist is already salivating over that prospect.
Ron
Ronny, Ronny, Ronny...
"The real tragedy here is that sailing vessels were here doing humankind's work long before automobiles and should be accorded seniority. Maybe all bridges should be replaced by tunnels, because as the global warming brings higher water levels the bridge problem grows ever more acute. Not only that, but boat builders have come and gone but never asked for a tax payer bail out. I guess your achievements are only as good as today - no respect. My hat's off to Kevin Costner - three cheers to water world. But even there the dogma of the smokers is persistent - must be a human thing. Is it possible that one day we will have 5W/20W filling our veins? I'll bet some petro-chemist is already salivating over that prospect."
Holy cow. Where do I start?
1~Maybe all bridges should be replaced by tunnels. Yes I wanted a tunnel so boats did not have to wait to the top-o-hour.
2~as the global warming brings higher water levels the bridge problem grows ever more acute. WRONGO. No warming. Traffic won't have to wait either using tunnels. Tons in Germany to save a pond.
3~boat builders have come and gone but never asked for a tax payer bail out. PJ's and Fincintara have. And got it.
4~My hat's off to Kevin Costner - three cheers to water world Liberal Hollywood hype. Bull Hockey. To be sure.
5~dogma of the smokers is persistent Yep. Smoking is for suckers.
6~Is it possible that one day we will have 5W/20W filling our veins? Dr. House says, "Unlikely. But run feesability tests."
7~I'll bet some petro-chemist is already salivating over that prospect I'm pretty sure that's incorrect as well.
skip.