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Steve December 18th 08 12:55 AM

Todays problem
 

On Thu, 18 Dec 2008 00:21:42 +0000, Gordon wrote:

Brian Whatcott wrote:
On Wed, 17 Dec 2008 18:25:22 +0000, Gordon wrote:

You have run aground. Your boat draws 6 feet when upright.
You think you can heel your boat 10 degrees by kedging with an anchor.
How much is is this going to reduce your draft?

Now, your toerail is underwater at 30 degrees of heel.
What will your draft be now?
g


6 sin 80 is about 5ft 10.8 in (heel 10 deg).
6 sin 60 is about 5. ft 2.4 in. heel 30 deg)
6 sin45 is about 4 ft 3 in (heel 45deg)

Brian W


Very good, As you can see 10 deg heel didn't give you a heck of a lot.
Gordon


You're assuming a simple fin keel. You really do have to know the
shape of the bottom. For instance, say it's a theoretical round
bottom. Heeling won't change the draft at all.

But now say it's a real boat with a twin keel. Heeling 10 degrees, or
even 30 degrees may increase the draft.

But if it's a real boat with a wing keel, heeling 10 degrees will
probably increase the draft while 30 degrees may or may not decrease
the draft depending on the size of the wing.

Steve

[email protected] December 18th 08 01:02 AM

Todays problem
 
*You have run aground. Your boat draws 6 feet when upright.
*You think you can heel your boat 10 degrees by kedging with an anchor.
*How much is is this going to reduce your draft?



You could heel the boat a lot more by putting a couple of crew members
swung out on the boom.

Brian Whatcott wrote:
6 sin 80 is about 5ft *10.8 in * *(heel 10 deg).
6 sin 60 is about 5. ft 2.4 in. * heel 30 deg)
6 sin45 is about 4 ft 3 in * * (heel 45deg)




Gordon wrote:
* *Very good, As you can see 10 deg heel didn't give you a heck of a lot.
*


And as others have pointed out, it depends a lot on the beam & hull
shape of the boat.

You might well gain more by sending all crew up on the bow.

Fresh Breezes- Doug King


Larry December 18th 08 02:35 AM

Todays problem
 
wrote in news:03ac4c92-1c2b-40f7-9b95-
:

You might well gain more by sending all crew up on the bow.

Fresh Breezes- Doug King




We could blow the stern ballast tanks.....


Frogwatch December 18th 08 03:09 AM

Todays problem
 
On Dec 17, 9:35 pm, Larry wrote:
wrote in news:03ac4c92-1c2b-40f7-9b95-
:

You might well gain more by sending all crew up on the bow.


Fresh Breezes- Doug King


We could blow the stern ballast tanks.....


Being a trig geek, and assuming hull shape counts for nothing, 10
degrees gives you only about 1.' or 1.2 inches. Even 30 degrees dont
give give much.
OTOH, I know that heeling really does work for my boat so hull shape
does matter. I have gotten my boat into places she shouldnt have gone
by heeling her.

Frogwatch December 18th 08 03:14 AM

Todays problem
 
On Dec 17, 10:09 pm, Frogwatch wrote:
On Dec 17, 9:35 pm, Larry wrote:

wrote in news:03ac4c92-1c2b-40f7-9b95-
:


You might well gain more by sending all crew up on the bow.


Fresh Breezes- Doug King


We could blow the stern ballast tanks.....


Being a trig geek, and assuming hull shape counts for nothing, 10
degrees gives you only about 1.' or 1.2 inches. Even 30 degrees dont
give give much.
OTOH, I know that heeling really does work for my boat so hull shape
does matter. I have gotten my boat into places she shouldnt have gone
by heeling her.


In reality, I think what happens to me is that my keel is wide and
flat at the bottom presenting a wide surface to the low density mud.
Heeling presents a wedge shape to the low density mud allowing me to
actually motor through mud with the consistency of very stiff pudding.

Tom Dacon[_3_] December 18th 08 03:43 AM

Todays problem
 

"Gordon" wrote in message
m...
You have run aground. Your boat draws 6 feet when upright.
You think you can heel your boat 10 degrees by kedging with an anchor.
How much is is this going to reduce your draft?

Now, your toerail is underwater at 30 degrees of heel.
What will your draft be now?
g


For my boat, which draws 7'2" with a flat-bottomed keel that's about 18"
wide, heeling 10 degrees actually increases the draft by about a
quarter-inch (assuming that the boat does not rise or drop on account of the
heel angle).

Tom Dacon



Larry December 18th 08 05:20 AM

Todays problem
 
Frogwatch wrote in news:ca6b94d0-b5ed-414a-a25f-
:

On Dec 17, 9:35 pm, Larry wrote:
wrote in news:03ac4c92-1c2b-40f7-9b95-
:

You might well gain more by sending all crew up on the bow.


Fresh Breezes- Doug King


We could blow the stern ballast tanks.....


Being a trig geek, and assuming hull shape counts for nothing, 10
degrees gives you only about 1.' or 1.2 inches. Even 30 degrees dont
give give much.
OTOH, I know that heeling really does work for my boat so hull shape
does matter. I have gotten my boat into places she shouldnt have gone
by heeling her.


http://www.youtube.com/watch?v=epz6BBZm__0

Precisely why I'm more interested in this video to free her from the mud,
than I am to get her under that bridge. You could lay her on her side with
these boat balls and drive her off....without the towboat ripoff.


slide[_2_] December 18th 08 05:14 PM

Todays problem
 
Larry wrote:


http://www.youtube.com/watch?v=epz6BBZm__0

Precisely why I'm more interested in this video to free her from the mud,
than I am to get her under that bridge. You could lay her on her side with
these boat balls and drive her off....without the towboat ripoff.


Damn those ripoff artists in tugboats. Next time I'm stuck, I'm going to
call you for a FREE tow off the sandbar. You'll show those greedy
*******s who's boss!!


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