Thread: Todays problem
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Steve Steve is offline
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First recorded activity by BoatBanter: Mar 2007
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Default 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