Could someone please tell me what a knotical mile is in comparison to
the standard mile. Also what does D/L limited speed: 10.08 kt. and
Disp. Hull Speed: 5.90 kt. mean.
I am just fooling around with a hull designer and would appreciate any
info.

On Sat, 17 Jan 2004 09:45:54 GMT,
(Lou Dempster) wrote:

Could someone please tell me what a knotical mile is in comparison to
the standard mile.

A nautical mile is 6,080 feet (1853.18 meters) and is equal to 1/60th
of a degree of latitude. A statute mile is 5,280 feet.

Also what does D/L limited speed: 10.08 kt. and Disp. Hull Speed: 5.90 kt.
mean.

Just guessing here, but the D/L should be Displacement to Length Ratio
and don't aske me how you figure it because it has been a long time
and I'd have to look it up. However, it's basic explanation is that
the longer the boat at the waterline, the faster it is given it's
displacement (weight). For example, a boat weighing 1,000 pounds will
act like a boat weighing 2,000 pounds if you shorten the length at the
water line and vice versa - a 2,000 pound boat will act like a 1,000
pound boat if you lengthen the waterline. There are a couple of other
factors involved, but that's the basic gist of the term.

The Displacement Hull Speed is the speed at which the designed hull
will efficiently travel.

I am just fooling around with a hull designer and would appreciate any
info.

Have fun.

Later,

Tom
S. Woodstock, CT
----------
"My rod and my reel - they comfort me."

St. Pete, 12 Lb. Test

Short Wave Sportfishing wrote
A nautical mile is 6,080 feet (1853.18 meters)

Not quite. It is 1852 meters precisely.

If you aren't too fussy....a nautical mile is about 1 & 1/8th statute miles.
that is ...8 nautical miles = 9 road miles.

Lou Dempster wrote in message
...
Could someone please tell me what a knotical mile is in comparison to
the standard mile. Also what does D/L limited speed: 10.08 kt. and
Disp. Hull Speed: 5.90 kt. mean.
I am just fooling around with a hull designer and would appreciate any
info.

On 17 Jan 2004 09:54:23 -0800, (Pat Norton)
wrote:

Short Wave Sportfishing wrote
A nautical mile is 6,080 feet (1853.18 meters)

Not quite. It is 1852 meters precisely.

Correctomundo.

Later,

Tom
S. Woodstock, CT
----------
"My rod and my reel - they comfort me."

St. Pete, 12 Lb. Test

On Sat, 17 Jan 2004 19:51:22 GMT, Short Wave Sportfishing
wrote:

On 17 Jan 2004 09:54:23 -0800, (Pat Norton)
wrote:

Short Wave Sportfishing wrote
A nautical mile is 6,080 feet (1853.18 meters)

Not quite. It is 1852 meters precisely.

Correctomundo.

~~ continued from hitting the wrong key and sending early ~~

A nautical mile is also, precisely, 6,076.12 feet.

I look at it this way - if I can get within four feet of something, I
can holler at it. :)

Later,

Tom
S. Woodstock, CT
----------
"My rod and my reel - they comfort me."

St. Pete, 12 Lb. Test

[HAIRSPLITTING=ON]

On Sat, 17 Jan 2004 19:57:18 GMT, Short Wave Sportfishing
wrote:

A nautical mile is also, precisely, 6,076.12 feet.

That's not precise--that's rounded to two decimals.

A nautical mile is, by definition, precisely 1,852 meters, as mentioned above.

That converts to 6,076.11549 feet (which still is not precise!).

[HAIRSPLITTING=OFF]

I look at it this way - if I can get within four feet of something, I
can holler at it. :)

Now THAT is practical navigation!


Joe Parsons

On Sat, 17 Jan 2004 20:27:21 GMT, Joe Parsons
wrote:

[HAIRSPLITTING=ON]

On Sat, 17 Jan 2004 19:57:18 GMT, Short Wave Sportfishing
wrote:

A nautical mile is also, precisely, 6,076.12 feet.

That's not precise--that's rounded to two decimals.

A nautical mile is, by definition, precisely 1,852 meters, as mentioned above.

That converts to 6,076.11549 feet (which still is not precise!).

[HAIRSPLITTING=OFF]

I look at it this way - if I can get within four feet of something, I
can holler at it. :)

Now THAT is practical navigation!

Damn straight! :)

Later,

Tom
S. Woodstock, CT
----------
"My rod and my reel - they comfort me."

St. Pete, 12 Lb. Test

"Joe Parsons" wrote in message
...
[HAIRSPLITTING=ON]

On Sat, 17 Jan 2004 19:57:18 GMT, Short Wave Sportfishing
wrote:

A nautical mile is also, precisely, 6,076.12 feet.

That's not precise--that's rounded to two decimals.

A nautical mile is, by definition, precisely 1,852 meters, as mentioned
above.

That converts to 6,076.11549 feet (which still is not precise!).

[HAIRSPLITTING=OFF]

I look at it this way - if I can get within four feet of something, I
can holler at it. :)

Now THAT is practical navigation!


Joe Parsons


Difference between an engineer and a mathematician.

Voluptuous Dallas Cheer leader is standing nekid on the goal line.
The engineer and math nerd are on the other line. Told that the first one
to her gets her. Only restriction is can move only 1/2 the distance to the
goal in any one move. Math nerd says 'won't even start, is an infinite
series and will never get there.'. Engineer is moving and states, 7 moves
and I am close enough for any thing I want to do.

Joe, you a math minor in a business major?
Bill

Lou Dempster wrote:

Could someone please tell me what a knotical mile is in comparison to
the standard mile. Also what does D/L limited speed: 10.08 kt. and
Disp. Hull Speed: 5.90 kt. mean.
I am just fooling around with a hull designer and would appreciate any
info.

Well, other have answered the nautical mile question, so I'll try the
other two. Displacement hull speed is the highest speed a given hull can
reach when limited to it's wave train. What this means is that the boat is
fully supported by displacement of water (as opposed to planing, where the
boat is supported by hydrodynamic force of water going by under the hull)
and so therefore it has to push water out of the way, making waves. A less
obvious point is that the water has to come back together again as the
boat passes.... in traditional hull design, the key to designing a fast
boat was always said to be to minimize the stern wave.

Displacement hull speed is determined by waterline length. The further
apart the bow & stern waves are, the faster the connected wave train can
move across the surface. At 5.9 knots, the crests of the bow and stern
wave are about 18' 4" apart, so I bet that is the waterline length of the
hull you are designing.

D/L refers to the displacement/length ratio, which can affect whether the
boat is truly limited by it's wave train. A long skinny hull can go faster
relative to it's theoretical hull speed, that's how catamarans and Navy
destroyers reach higher speeds.

Hope this helps.

Fresh Breezes- Doug King