Sailboats and bridges

[billknny]

That ONE stupid video from 25 years ago of somebody doing this...makes everybody think it is a good idea, and that it is a routine thing.

If you google "supersack" you'll find the industrial bags you are looking for. A 35 cu ft bag will hold a long ton of water. Be sure to have a chase boat with video runing as you do it. We'd all love the chance to say, "I told you so!"

Have you ever tried to lift 1000 lbs with the average halyard winch on a 40 foot boat? I think you'll find it rather... difficult.

[slug]

Originally Posted by billknny

That ONE stupid video from 25 years ago of somebody doing this...makes everybody think it is a good idea, and that it is a routine thing.

If you google "supersack" you'll find the industrial bags you are looking for. A 35 cu ft bag will hold a long ton of water. Be sure to have a chase boat with video runing as you do it. We'd all love the chance to say, "I told you so!"

Have you ever tried to lift 1000 lbs with the average halyard winch on a 40 foot boat? I think you'll find it rather... difficult.

You don’t “ lift “ a ballast bag

You hang is dry , stabilized by the main boom or spi pole ...then fill the bag with a pump

To the original poster

It’s very hard to determine the height of a bridge

Best to measure it yourself
Careful with electric cables and lighting under the bridge

[Hudson Force]

Originally Posted by Andrew Hamilton

...................
............... If I wanted to remove the masts ( which I consider drastic and traumatic) ......................Facilities for popping masts in and out of their steps are few and far between in power boat country..............

Disconnecting the shrouds from their chain plates and lifting masts with a truck mounted crane or "cherry picker" is quite simple. This is usually accomplished by strapping the mast just under the spreaders. With the greater mass of the mast beneath the spreader, a hand line can easily control the maneuvering of the mast to guide it to rest. All the shrouds and stays can remain in place tied to the mast.

The "facilities" for lifting the mast are available everywhere there are elevated advertising signs. Vehicles that are available to rent for erecting and maintaining signs and billboards are well suited for lifting masts.

Of course, go with your choice, but I would consider pulling the mast as far less drastic and traumatic.

[LittleWing77]

Is it just me, or does anyone else stop reading a thread when a poster is rude to Ann or Jim Cate?

LittleWing77

[letsgetsailing3]

Originally Posted by LittleWing77

Is it just me, or does anyone else stop reading a thread when a poster is rude to Ann or Jim Cate?

LittleWing77

I think most people just take a break to get some popcorn.

[dannc]

Originally Posted by LittleWing77

Is it just me, or does anyone else stop reading a thread when a poster is rude to Ann or Jim Cate?

LittleWing77

I do not/did not stop reading but rudeness reflects poorly on the OP. It really reflects poorly on the OP when they insult The Cate's.

A newbie to a forum should be more careful in posting. Especially, when they ask for advice, and while the advice might not be one wants to hear, it is danged good advice.

Later,
Dan

[Montanan]

Originally Posted by Andrew Hamilton

I have a 41ft ketch. I have just purchased in providence to live on. I am planning to sail her around a half loop to Chattanooga. I will berth there while my sons go thru highschool. My question is where can I find water weight bags that can be used repeatedly for heeling my boat over to clear low hanging bridges upstream to Chattanooga . Commercial weight bags , retail.

So the intent is to take the ketch to Chattanooga via the river to have a liveaboard vessel. It seems there will be little to no opportunity to actually sail, instead the boat will be powered if it leaves a dock. Seems like a practical solution would be to lower the masts and store them on raised deck supported mounts, wherein the masts could be used to support semi-permanent tenting to cover the boat while it is at dock or perhaps stored on the hard for liveaboard purposes.

Why would one want to keep the masts up when it is not in sailing country for several years? Just asking.

[Montanan]

https://www.lrn.usace.army.mil/Missi...-River-Charts/List of vertical clearance for bridges on the Tennessee - Tombigbee waterway.

https://www.sam.usace.army.mil/Porta...av/bridges.pdf

Charts:

https://www.sam.usace.army.mil/Porta...rts_072012.pdf

[Montanan]

Originally Posted by tkeithlu

Look at it another way, Andrew. When you cant your boat 20 degrees, which will take a lot of weight to overcome the moment arm of your keel, your mast will still be 0.94 x 58' = 54.5'.

Many of the bridge vertical clearances on the Tom-Tig are as low as 52 feet at "normal pool". So best plan to tilt over to say 50 feet or less and to traverse when the pool is not high.

Considerable tilts will be required.

Don't know about the rest of the bridge clearances on the lower river or on the Tennessee.

Also one has to plan for clearing the numerous power lines that cross the water ways. Review the charts along the many hundreds of miles to ascertain all the points of concern.

Hope you and your sons will enjoy Chattanooga region. All the best.

[slug]

Originally Posted by Montanan

Many of the bridge vertical clearances on the Tom-Tig are as low as 52 feet at "normal pool". So best plan to tilt over to say 50 feet or less and to traverse when the pool is not high.

Considerable tilts will be required.

Don't know about the rest of the bridge clearances on the lower river or on the Tennessee.

Also one has to plan for clearing the numerous power lines that cross the water ways. Review the charts along the many hundreds of miles to ascertain all the points of concern.

Hope you and your sons will enjoy Chattanooga region. All the best.

Don’t get anywhere near a marginal clearance power line

Precise Height above the water is never known

[CFS Klopas]

The clearances on those bridges are only 54' at low water. The "regulated high water" clearance in flood conditions on the bridges is as low as 32'.

https://www.lrn.usace.army.mil/missi...-river-charts/

[Jammer]

Originally Posted by Andrew Hamilton

I have a 41ft ketch. I have just purchased in providence to live on. I am planning to sail her around a half loop to Chattanooga. I will berth there while my sons go thru highschool. My question is where can I find water weight bags that can be used repeatedly for heeling my boat over to clear low hanging bridges upstream to Chattanooga . Commercial weight bags , retail.

There are ballast bags that attach to the toerail that would be more suitable for repeated use than a bag suspended from the halyard.


MAXI MARINE - External Water Ballast System for Sailboats - Turbo Boatabag Specification and Price

Originally Posted by tkeithlu

I agree with Jim Cate, of course. In addition:

We came downstream from Chattanooga to Mobile Bay. I don't remember ever having less than the usual 65' clearance on that route, although we need only 28' and possibly missed one. How tall are your masts?

Originally Posted by Andrew Hamilton

tkeithlu that is wonderful info. My mainmast is approximately 58ft. The Market st. Bridge is about 60 something dependent upon water level maintained by TVA. I will probably have to be vigilant with some of these up river bridges. I would love to have a water bag as a quick option. As opposed to swinging my wooden Dory out.

There are numerous bridges on the Tennesee-Tombigbee Waterway that are charted at 52' above pool. River levels are carefully controlled -- materially higher or lower water levels (by more than about a foot) are unusual. These are newer bridges and are all or nearly all close to straight across so you cannot pick up any clearance from the arch as is the case elsewhere. It is unclear to me from you post whether you intend to navigate the Tenn-Tom with the mast up, but I would not recommend it.


You may want to check clearance for the lock at the foot of Pickwick Lake. There are two chambers, with the auxiliary one having the most clearance, again at 57' feet from "pool". I would be surprised if the ACOE would allow you to lock through with a forced heel, but perhaps they would. A fact to consider is that Pickwick Lake water levels vary widely and "pool" is more of a guideline, and the lake may be several feet (or more) above or below "pool" on any given day. The vertical clearance in the locks doesn't appear in the light list, only in some of the paper charts, and may have changed since they were published. Something to check.


There is also a powerline at R.M. 333 in some of the charts that doesn't appear in the light list. I don't know if it's still there.

[CFS Klopas]

The hard part of this isn't going to be the Ten-Tom, it's going to be the Upper Tennessee River.

[Montanan]

On the Tennessee River: Water level is a key factor.

The Southern Railroad Bridge at mile 647.3 has a stated vertical clearance of only 50 feet at normal pool

The Southern Railroad Bridge at mile 591.3 has a vertical clearance of 61.8 feet above normal pool, 49.4 feet above regulated high water.

On the TENNESSEE-TOMBIGBEE WATERWAY:

Numerous 52 feet bridges.

But limiting is the Southern Railroad Bridge at mile 436 the vertical clearance is 49 feet at normal pool.

Reference the last pages of this Light List which in alphabetical order so the T waterways are listed at the back:

https://www.navcen.uscg.gov/pdf/ligh...hlyChanges.pdf

[Montanan]

Originally Posted by tkeithlu

Look at it another way, Andrew. When you cant your boat 20 degrees, which will take a lot of weight to overcome the moment arm of your keel, your mast will still be 0.94 x 58' = 54.5'.

To get below the 49 feet clearance of the railroad bridge at normal pool will require something like 32 to 35 degree tilt. The weight of which is not something that I perceive a halyard would likely support safely.