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11-09-2018, 15:38
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#1
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Moderator
Join Date: Jan 2010
Location: Minnesota
Boat: Tartan 3800
Posts: 4,848
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Induced heel for bridge clearance
There are a number of sailing blogs and videos that report the use of induced heel to proceed under a bridge that would otherwise have insufficient clearance.
- Is this a widespread practice?
- Is it safe?
- What are the practical and safe limits of induced heel?
- What is the most practical and safest way to induce heel when the need for it can be anticipated far enough in advance to prepare?
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12-09-2018, 06:58
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#2
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Registered User
Join Date: Jul 2012
Location: New England
Posts: 356
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Re: Induced heel for bridge clearance
Sketchy at best, only takes one variable to turn those moves into a real cluster imo. Any incident will require the bridge be closed to vehicle traffic until engineering dept can reinspect it.
Not a practice recommended by insurance carriers lol!
__________________
"Simplicity made the boat a pleasure to sail"
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12-09-2018, 08:22
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#3
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Registered User
Join Date: Apr 2016
Location: Nola
Boat: 97 Hunter 430 43 ft.
Posts: 369
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Re: Induced heel for bridge clearance
there are places along the ICW where this is fairly common. I am sure your equipment condition has a lot to do with how safe it is. I would use back up lines so i don't "pop" up, but it wouldn't scare me that much. there was someone selling a bag designed for this, but most use barrels in a net or tarp. near some of the more notorious areas I believe there are some vendors who will bring the supplies to you and offer some advice.
http://www.trevorowenltd.com/water_bladder_bags.htm something like this
depending on size of boat
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12-09-2018, 08:49
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#4
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Moderator Emeritus
Join Date: Sep 2007
Location: Eastern Tennessee
Boat: Research vessel for a university, retired now.
Posts: 10,406
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Re: Induced heel for bridge clearance
Clever idea with the ladder and the person sitting on the end of it.
__________________
David
Life begins where land ends.
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12-09-2018, 09:08
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#5
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Registered User
Join Date: May 2008
Posts: 3,536
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Re: Induced heel for bridge clearance
This is not common. In four trips up an down the ICW, I've only seen it on You Tube.
If you do a bit of trigonometry, you'll find that you need to heel the boat 20 degrees to make a big difference. And this isn't easy. But if you need just a few inches, anything is worth a try.
But I once did put some heel in the boat by running the main halyard through a block in the end of the boom and tied to a lifting bridle on the RIB. I put two 200lb guys in the dingy and swung the boom out and winched the halyard. I didn't actually lift the dinghy out of the water just pulled the boat down to it some. It was easy to control since the guys in the dinghy had ropes to keep it straight as we went through. I even thought about having them start the outboard to help keep the dinghy centered but didn't need it. This got a couple of feet of the height. I wouldn't have dared to try to get more height because of the the strain and control issues.
We also waited to go through until there was no current and no other boats anywhere nearby that would crowd the passage or create a wake.
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12-09-2018, 09:10
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#6
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Registered User
Join Date: Jan 2011
Location: Caribbean live aboard
Boat: Camper & Nicholson58 Ketch - ROXY Traverse City, Michigan No.668283
Posts: 6,367
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Re: Induced heel for bridge clearance
My favorite. This guy is about our size. Lynn says NO.
Basically, your rig needs to be this strong or the boat is just a day sailer.
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12-09-2018, 09:14
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#7
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Registered User
Join Date: Jan 2011
Location: Caribbean live aboard
Boat: Camper & Nicholson58 Ketch - ROXY Traverse City, Michigan No.668283
Posts: 6,367
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Re: Induced heel for bridge clearance
Quote:
Originally Posted by Tkeeth
there are places along the ICW where this is fairly common. I am sure your equipment condition has a lot to do with how safe it is. I would use back up lines so i don't "pop" up, but it wouldn't scare me that much. there was someone selling a bag designed for this, but most use barrels in a net or tarp. near some of the more notorious areas I believe there are some vendors who will bring the supplies to you and offer some advice.
Water Bladder Bags Aqua Tank something like this
depending on size of boat
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This is a very tender boat. I assume the OP is dealing with the ICW, 63 feet. More mass, bigger boat. Nice video, new to me.
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12-09-2018, 11:48
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#8
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Moderator
Join Date: Jan 2010
Location: Minnesota
Boat: Tartan 3800
Posts: 4,848
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Re: Induced heel for bridge clearance
I'm actually trying to inform a purchase for a boat that will be on the Mississippi and Tenn-Tom. Controlling clearance for various segments is 60', 55', and 52' over normal pool. There is considerable variation in pool at some of the bridges. Air draft for the boats I'm looking at runs from about 50-60'.
It's possible to remove the mast, and many boats do on these routes, particularly since it is not possible to get through Chicago any other way. But since I am in the Minneapolis area and expect to have connections here for quite some time, I have reasons to get to the Gulf without necessarily going through Chicago. That opens up alternatives for completing the trip without unstepping the mast, as long as the boat is well chosen.
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12-09-2018, 12:05
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#9
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running down a dream
Join Date: Mar 2006
Location: Florida
Boat: cape dory 30 MKII
Posts: 3,115
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Re: Induced heel for bridge clearance
they do it at the fixed bridge on Okeechobee waterway. one service there fills up plastic 50 gallon barrels on your side deck. we filled 5 gallon jugs with water and tied them to the end of the boom. depends on how much you want to stress your rig and how much your boat needs to lean over.
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some of the best times of my life were spent on a boat. it just took a long time to realize it.
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12-09-2018, 12:49
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#10
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Registered User
Join Date: Jan 2011
Location: Caribbean live aboard
Boat: Camper & Nicholson58 Ketch - ROXY Traverse City, Michigan No.668283
Posts: 6,367
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Re: Induced heel for bridge clearance
I saw a 78 foot yacht years ago that had a mast hinged at the deck. Shrouds also pinned to hint and in line with the mast pin. The windlass was used to drop the mast over the pilot house. The owner was 78
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12-09-2018, 13:06
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#11
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Registered User
Join Date: May 2008
Posts: 3,536
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Re: Induced heel for bridge clearance
If you are willing to modify the rig substantially, I once saw a marvelous system on a ketch. A line went to a block at the top of the mizzen mast. A second line was led through a cheek block set about 2/3s of the way up the mainmast.
When it was time to lower the mainmast, the forward lower shrouds were removed and the mizzen top line was attached to the mainmast line and tightened.
A line was lead through a block on the bow and attached to the base of the headstay and lead to a winch. The headstay was then slowly let off while the line to the mizzen was tightened until the mainmast was resting on the top of the mizzen mast. The block on the mainmast had been placed at the right height so it would come down exactly on the top of the mizzen mast.
This took about 10ft off the height of the rig. Everything was quite secure and the mainmast was not in the way on deck. Since the mast only went down about 40 degrees, the strains on the lifting gear was not extreme.
She did look very strange
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12-09-2018, 13:08
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#12
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Registered User
Join Date: Aug 2016
Posts: 988
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Re: Induced heel for bridge clearance
Quote:
Originally Posted by CarlF
If you are willing to modify the rig substantially, I once saw a marvelous system on a ketch. A line went to a block at the top of the mizzen mast. A second line was led through a cheek block set about 2/3s of the way up the mainmast.
When it was time to lower the mainmast, the forward lower shrouds were removed and the mizzen top line was attached to the mainmast line and tightened.
A line was lead through a block on the bow and attached to the base of the headstay and lead to a winch. The headstay was then slowly let off while the line to the mizzen was tightened until the mainmast was resting on the top of the mizzen mast. The block on the mainmast had been placed at the right height so it would come down exactly on the top of the mizzen mast.
This took about 10ft off the height of the rig. Everything was quite secure and the mainmast was not in the way on deck. Since the mast only went down about 40 degrees, the strains on the lifting gear was not extreme.
She did look very strange
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Interesting. The one thing I would add to this though, is a ketch is already a much shorter rig. Might be something for Jammer to consider. My 42' ketch has only a 48' tall rig. I slip under all sorts of bridges other boats with my LOA can't.
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12-09-2018, 13:09
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#13
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Registered User
Join Date: Jun 2008
Location: Tampa, FL
Posts: 5,014
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Re: Induced heel for bridge clearance
Quote:
Originally Posted by Jammer
Controlling clearance for various segments is 60', 55', and 52' over normal pool. There is considerable variation in pool at some of the bridges... Air draft for the boats I'm looking at runs from about 50-60'.
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If you want to get a 60' mast down to 52' you have to heel the boat over by about 30 degrees. That's a lot of heel.
Of course, some boats can be perfectly stable at that sort of heel. Some, in fact, can easily be sailed at that sort of a heel. Others, not so much. So whether it is safe (or even possible) depends on a lot of different design factors of the boat.
Personally, I think that in the long run it would be a whole lot easier to just unstep the mast. After all, you surely aren't planning to go up and down the Mississippi every year, the way people go up and down the ICW, are you?
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12-09-2018, 15:01
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#14
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Moderator
Join Date: Jan 2010
Location: Minnesota
Boat: Tartan 3800
Posts: 4,848
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Re: Induced heel for bridge clearance
Quote:
Originally Posted by denverd0n
If you want to get a 60' mast down to 52' you have to heel the boat over by about 30 degrees. That's a lot of heel
[...]
Personally, I think that in the long run it would be a whole lot easier to just unstep the mast. After all, you surely aren't planning to go up and down the Mississippi every year, the way people go up and down the ICW, are you?
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The ideas I'm exploring are whether, for example, a boat with 53' air draft (after removal of windex, anchor light, antennas, etc) could reasonably be taken down the Tenn-Tom, where it would have to clear around seven bridges with a charted clearance of 52'-53' over normal pool (not including bridges that clearly have a higher-clearance area outside the bounding horizontal and vertical rectangle reported in ACOE publications).
Or, similarly, whether a boat with 61' air draft could reasonably be taken down the Mississippi under the three bridges that have reported clearance between 60' and 61'.
This drives both boat purchasing and ideas on what home ports are reasonable for us. Stillwater and Duluth are separated by 150 miles on land (and a continental divide) -- one is on the Mississippi river system, and one is on the Lake Superior. Each is a possible home port. From Duluth, there are no practical limits on clearance all the way to the Atlantic. From Stillwater, it's 60' over normal pool via New Orleans and 52' over normal pool via Mobile. Of all of these, the outbound trip via Mobile is widely regarded as being the most enjoyable, but it has the least clearance.
For return trips, mast height doesn't play much of a role. Returning to Duluth again has no practical limits on clearance. Returning to Stillwater either involves dropping the mast in Chicago and motoring up from Cairo, or hauling the boat in Duluth and having it shipped the last 150 miles -- which could very well be the most sensible choice if it is scheduled at a time when the boat needs to be hauled for maintenance anyway.
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13-09-2018, 12:13
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#15
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Registered User
Join Date: Sep 2010
Location: Oregon City, OR
Boat: 37 Uniflite Coastal Cruiser
Posts: 800
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Re: Induced heel for bridge clearance
We had a major ** when a sailboat tried to do this underneath a railroad bridge across the Columbia River a few years ago. The boat popped up enough while passing under the bridge that the mast caught between two of the steel support beams. The boat was proceeding downstream, so the current forced the transom under the water. The boat swamped and left the crew swimming. The other part of the story was that none of this was necessary. The bridge has a swing span, but the boat didn't want to wait 15 or 20 minutes until an expected train was clear.
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