Submarines, Car Engines, and Displacement
 

I've had a few random questions rattling around the

brain for a while - figured I'd pose them there.



When a sub dives to a certain depth, is that depth

measured from the bottom of the sub, the middle,

or the top. In other words, if it dives to 200 feet,

does that mean there is 200 feet of water above

it or that the bottom of it is 200 feet below the

surface?



On modern gas car engines and when it's cold

outside, is it still better to let them warm up a

bit and how warm (how long) is necessary?



Anyone have a good way to find the total surface

area of my boat hull while it's in the water? It's

a 22' boat, not very deep V, "square" transom. I

did some estimating, but wonder if there are any

creative ways to get more accurate.



Gary

Submarines, Car Engines, and Displacement
 

On Tue, 6 Jan 2004 19:24:30 -0500, "Gary Warner"
wrote:

I've had a few random questions rattling around the

brain for a while - figured I'd pose them there.



When a sub dives to a certain depth, is that depth

measured from the bottom of the sub, the middle,

or the top. In other words, if it dives to 200 feet,

does that mean there is 200 feet of water above

it or that the bottom of it is 200 feet below the

surface?



On modern gas car engines and when it's cold

outside, is it still better to let them warm up a

bit and how warm (how long) is necessary?



Anyone have a good way to find the total surface

area of my boat hull while it's in the water? It's

a 22' boat, not very deep V, "square" transom. I

did some estimating, but wonder if there are any

creative ways to get more accurate.



Gary


Gary, I can tell you only that the surface area of your boat is the
same both in and out of the water.

John H

On the 'Poco Loco' out of Deale, MD
on the beautiful Chesapeake Bay!

Submarines, Car Engines, and Displacement
 

Gary Warner wrote:


When a sub dives to a certain depth, is that depth
measured from the bottom of the sub, the middle,
or the top. In other words, if it dives to 200 feet,
does that mean there is 200 feet of water above
it or that the bottom of it is 200 feet below the
surface?

Normally "depth to keel."


On modern gas car engines and when it's cold
outside, is it still better to let them warm up a
bit and how warm (how long) is necessary?

RTFM

Anyone have a good way to find the total surface
area of my boat hull while it's in the water? It's
a 22' boat, not very deep V, "square" transom. I
did some estimating, but wonder if there are any
creative ways to get more accurate.

Assuming you are seeking the "wetted area" rent one of those laser
thingys that scan a surface into a computer. Turn your boat on its side
and scan. Read computer generated results.

Rick

Submarines, Car Engines, and Displacement
 

When a sub dives to a certain depth, is that depth
measured from the bottom of the sub, the middle,
or the top. In other words, if it dives to 200 feet,
does that mean there is 200 feet of water above
it or that the bottom of it is 200 feet below the
surface?

Normally "depth to keel.

I don't know squat diddly about submarines, but I think I can answer this
question. *If* the dive indicator reads "zero" when the sub is on the surface,
the submerged depth would be measured from the normally ballasted waterline to
the surface. It wouldn't seem logical, otherwise.

Submarines, Car Engines, and Displacement
 

On Tue, 6 Jan 2004 19:24:30 -0500, "Gary Warner"
wrote:
I've had a few random questions rattling around the
brain for a while - figured I'd pose them there.

When a sub dives to a certain depth, is that depth
measured from the bottom of the sub, the middle,
or the top. In other words, if it dives to 200 feet,
does that mean there is 200 feet of water above
it or that the bottom of it is 200 feet below the
surface?

Interesting question but I have no idea.

On modern gas car engines and when it's cold
outside, is it still better to let them warm up a
bit and how warm (how long) is necessary?

Not necessary at all assuming everthing is in tune and the engine is
running smoothly. Just don't over rev the engine until it's up to
operating temperature, usually within a few miles.

Anyone have a good way to find the total surface
area of my boat hull while it's in the water? It's
a 22' boat, not very deep V, "square" transom. I
did some estimating, but wonder if there are any
creative ways to get more accurate.

If you piece it out into a rectangle and a triangle on each side, you
can get pretty close with a deep V hull. Given the deadrise angle and
length we could develop a trig formula that would be a good
approximation, but it's easier to piece it out, and you'll have a
better intuitive sense of the answer. (Length x Beam) + a small fudge
factor will also get you pretty close.

Submarines, Car Engines, and Displacement
 

"Gary Warner" wrote in message
...
I've had a few random questions rattling around the

brain for a while - figured I'd pose them there.



When a sub dives to a certain depth, is that depth

measured from the bottom of the sub, the middle,

or the top. In other words, if it dives to 200 feet,

does that mean there is 200 feet of water above

it or that the bottom of it is 200 feet below the

surface?


8 years on submarines and it is bottom of keel. Most
subs read about 65 feet at periscope depth which has
the sail about 5 to 10 feet below the surface.



On modern gas car engines and when it's cold

outside, is it still better to let them warm up a

bit and how warm (how long) is necessary?

Not an expert but, cold starts are a major
cause of engine wear. The oil is too thick to get
through all the passages quickly. Yes, let it warm
at least a little before raising rpm's to drive.





Anyone have a good way to find the total surface

area of my boat hull while it's in the water? It's

a 22' boat, not very deep V, "square" transom. I

did some estimating, but wonder if there are any

creative ways to get more accurate.

No idea!!

Submarines, Car Engines, and Displacement
 

8 years on submarines and it is bottom of keel. Most
subs read about 65 feet at periscope depth which has
the sail about 5 to 10 feet below the surface.

Fascinating. What does the depth indicator say when the sub is surfaced?
Obviously it would not be zero.

Submarines, Car Engines, and Displacement
 

The experts say in cold weather (below freezing) to warm the car up for a
couple of minutes and then drive away at a moderate pace.
Apparently it's much easier on the engine.... very inefficient to let a car
sit at idle...as oil not circulated as well as when on the move.

Gary Warner wrote in message

On modern gas car engines and when it's cold

outside, is it still better to let them warm up a

bit and how warm (how long) is necessary?

Submarines, Car Engines, and Displacement
 

"Wayne.B" wrote in message
...
On Tue, 6 Jan 2004 19:24:30 -0500, "Gary Warner"
wrote:
I've had a few random questions rattling around the
brain for a while - figured I'd pose them there.

When a sub dives to a certain depth, is that depth
measured from the bottom of the sub, the middle,
or the top. In other words, if it dives to 200 feet,
does that mean there is 200 feet of water above
it or that the bottom of it is 200 feet below the
surface?

Interesting question but I have no idea.

On modern gas car engines and when it's cold
outside, is it still better to let them warm up a
bit and how warm (how long) is necessary?

Not necessary at all assuming everthing is in tune and the engine is
running smoothly. Just don't over rev the engine until it's up to
operating temperature, usually within a few miles.

Anyone have a good way to find the total surface
area of my boat hull while it's in the water? It's
a 22' boat, not very deep V, "square" transom. I
did some estimating, but wonder if there are any
creative ways to get more accurate.

If you piece it out into a rectangle and a triangle on each side, you
can get pretty close with a deep V hull. Given the deadrise angle and
length we could develop a trig formula that would be a good
approximation, but it's easier to piece it out, and you'll have a
better intuitive sense of the answer. (Length x Beam) + a small fudge
factor will also get you pretty close.

When the boat is in the water, draw a line on the side a short distance
above the water line, say 1 inch, with a grease pencil or sharpie
marker. Then when the boat is out, use a 1 foot square of cardboard and
trace around it to make a grid from the keel to the waterline. Only
have to do half the boat, and so only will have maybe 50 or 60 squares.
you could make smaller rectangles or triangles to fill in gaps if you
are going for ultimate accuracy.

Suggestion 2. Instead of the squares, cut black plastic and tape to
exactly cover wetted surface. Weigh on accurate scale. Weigh a known
area. divide.

del cecchi

Submarines, Car Engines, and Displacement
 

On 07 Jan 2004 02:04:19 GMT, (Gould 0738) wrote:

When a sub dives to a certain depth, is that depth
measured from the bottom of the sub, the middle,
or the top. In other words, if it dives to 200 feet,
does that mean there is 200 feet of water above
it or that the bottom of it is 200 feet below the
surface?

Normally "depth to keel.

I don't know squat diddly about submarines, but I think I can answer this
question. *If* the dive indicator reads "zero" when the sub is on the surface,
the submerged depth would be measured from the normally ballasted waterline to
the surface. It wouldn't seem logical, otherwise.

You want to read depth to keel because you want it to be consistent with
the depth markings on charts. If the depth was to anywhere else, you'd
have to figure that in and it can contribute to mistakes that might
cause a grounding. I.e., if you're in an area where the min charted
depth is 250 feet, you can order a 200 foot depth safely. If it was
measured to the top and you ordered a 200 foot depth in 250 feet of
water, you'd hit the bottom.

Steve

Submarines, Car Engines, and Displacement
 

On 07 Jan 2004 02:52:36 GMT, (Gould 0738) wrote:

8 years on submarines and it is bottom of keel. Most
subs read about 65 feet at periscope depth which has
the sail about 5 to 10 feet below the surface.

Fascinating. What does the depth indicator say when the sub is surfaced?
Obviously it would not be zero.

That would depend on how far it surfaced. Did it blow all ballast or is
it just barely surfaced?

Steve

Submarines, Car Engines, and Displacement
 

On 07 Jan 2004 02:52:36 GMT, (Gould 0738) wrote:

Fascinating. What does the depth indicator say when the sub is surfaced?
Obviously it would not be zero.

We used to see subs on the surface all the time in eastern Long Island
Sound (sub base at Groton, CT). Only the conning tower and maybe 6
to 8 feet of hull is exposed at most when they are surfaced.
Estimating that the conning tower is submerged by 10 feet at periscope
depth, the height of the tower at 20 feet, plus 8 feet of hull - that
would put you about 38 feet above the periscope depth reading.

If you motor up the Thames River from New London, CT, you can actually
see partially assembled cross sections of subs on dry land. They look
incredibly big, even from a distance. And you really don't want to
take a lot of pictures or try to get closer. :-)

Submarines, Car Engines, and Displacement
 

Gould 0738 wrote:

It wouldn't seem logical, otherwise.

Posting an answer to something I know nothing about is illogical.

Rick

Submarines, Car Engines, and Displacement
 

"Wayne.B" wrote in message
...
On 07 Jan 2004 02:52:36 GMT, (Gould 0738) wrote:

Fascinating. What does the depth indicator say when the sub is surfaced?
Obviously it would not be zero.

We used to see subs on the surface all the time in eastern Long Island
Sound (sub base at Groton, CT). Only the conning tower and maybe 6
to 8 feet of hull is exposed at most when they are surfaced.
Estimating that the conning tower is submerged by 10 feet at periscope
depth, the height of the tower at 20 feet, plus 8 feet of hull - that
would put you about 38 feet above the periscope depth reading.

If you motor up the Thames River from New London, CT, you can actually
see partially assembled cross sections of subs on dry land. They look
incredibly big, even from a distance. And you really don't want to
take a lot of pictures or try to get closer. :-)


Even worse is to be boating when a sub comes by on the surface. The bow
wake is HUGE! Have to be careful when one is entering or exiting SF Bay to
avoid being swamped. Normal is a CG escort, so there is warning.
Bill

Submarines, Car Engines, and Displacement
 

Fascinating. What does the depth indicator say when the sub is surfaced?
Obviously it would not be zero.

That would depend on how far it surfaced. Did it blow all ballast or is
it just barely surfaced?

Steve


It can't blow enough ballast to put the keel on the surface. My point is merely
that if the depth is measured between the surface and the keel, (and I have no
reason to doubt that it is) there could never be a "zero" reading.

Submarines, Car Engines, and Displacement
 

Posting an answer to something I know nothing about is illogical.

Rick

I don't dispute that- ergo the disclaimer.
But if the depth is measured from the keel and there is a depth indicator on
the sub it will never read zero. Is that somehow incorrect? That was why I
postulated *if* a depth guage read zero at the surface the reading would have
to be from the normally ballasted waterline. Since it apparently does not read
zero, that theory doesn't fly. Freely admitted.

Submarines, Car Engines, and Displacemen
 

Gary Warner wrote:
I've had a few random questions rattling around the

brain for a while - figured I'd pose them there.



When a sub dives to a certain depth, is that depth

measured from the bottom of the sub, the middle,

or the top. In other words, if it dives to 200 feet,

does that mean there is 200 feet of water above

it or that the bottom of it is 200 feet below the

surface?

Depth below the surface, but pass on which part of the boat they
measure from. It's really just a measure of pressure on the hull not
"depth" as such, but the result is the same; unless it's in warm fresh
water:-)


On modern gas car engines and when it's cold

outside, is it still better to let them warm up a

bit and how warm (how long) is necessary?

Modern?? with modern multigrade oils??? A little warmup while you fix
the phone & belt up etc is OK but don't leave it just idling. The best
thing is to get it up to thermostat temp as soon as possible & to do
that it's best making some power (it takes forever if just left idling).
On the other side don't jump in a cold engine & take it to max power,
revs etc, that's not sensible either.




Anyone have a good way to find the total surface

area of my boat hull while it's in the water? It's

a 22' boat, not very deep V, "square" transom. I

did some estimating, but wonder if there are any

creative ways to get more accurate.

From your thread title I think you want the "volume" of the hull below
the water line??? not the area??? Also your question seems to suggest
"while it's in the water"?? you want to work this out without pulling
the boat out??

For the surface area, most of the anitfoul paints, either on the tin or
a pamphlet, have a simple method to work out how much paint you'll need.
But they're not too accurate.

To measure surface area accurately you'll need to measure 1/2 the
bottom of the boat & that part of the sides (if a chine boat) below the
waterline, where ever possible reduce it to oblongs or squares, then
various right triangles when you run out of easy oblongs etc. Add them
all together, double it & that's the total surface area.

In boat design they use a planimeter to run over the lines.

To calculate the "displacement" (volume of the boat below the
waterline) you can actually get a pretty accurate measurement by using
"simpson's formula" even as your question seems to suggest, with the
boat still in the water by;

(i) Boats are usually designed on 10 "sections" i.e. notionally the boat
has 11 transverse stations/bulkheads across it equal distance apart from
the waterline bow. Say a 30 ft WL boat they'd be 3ft apart?? These
stations/bulkheads are not "real", although usually bulkheads are at a
station point, but whatever but you can easily measure with a tape what
the below waterline areas would be, even on a bigger boat.

(ii) You need to measure the "area" of each of those notional
stations/bulkheads, but just that area which is below the waterline.
(again designers with plans drawings etc run around the 1/2 shape X3 div
by 3 to average with a planimeter)

(iii) Once you know the below the waterline only area in sq ft of each
of the boat's 10 notional stations, you multiple each by simpson's
multipliers 1,4,2,4,2,4,2,4,2,4,1 (11 notional below waterline
stations/bulkheads gives 10 equal length sections of the boat)

(iv) Add all the answers together so you now have the sum of functions.

(v) Use simpson's formula to work out the boat or ship's current
displacement per;

2 X 1/3 X sum of functions of 1/2 areas X (inverted scale)sq X the
common interval X 64 = displacement in ponds of salt water, or for fresh
water use 62.2 as the last figure.

This is the formula as used in boat design, so it is a bit more yuk
than you need, all you need is;

(a) 2 is to account for only using 1/2 the below waterline
station/bulkhead area, you can leave it out if you measured the full sq
ft of each area before using his multipliers.

(b) 1/3 is just part of the formula.

(c) Sum of the functions is explained in (iv) above. (but designers
tend to just use 1/2 then multiply by 2 see (a))

(d) Inverted scale squared doesn't bother you because you can use feet
as a direct measure, whereas a designer might be using say 1/2" to the
foot in their drawings. So make sure your notional below the waterline
areas or 1/2 areas if you choose, are in sq ft.

(e) Common interval is the length in feet of each section, again say
it's waterline length of 30 ft the "common interval" is 3.

(f) At this point the formula should have delivered you the boat's
below the waterline volume in cubic feet, the 64 is just the weight in
pounds of a cubic ft of salt water, or 62.2 for fresh water; to give you
the displacement in lbs (weight of the boat).

K




Gary

Submarines, Car Engines, and Displacement
 

On Tue, 06 Jan 2004 19:24:30 -0500, Gary Warner wrote:


Anyone have a good way to find the total surface

area of my boat hull while it's in the water? It's

a 22' boat, not very deep V, "square" transom. I

did some estimating, but wonder if there are any

creative ways to get more accurate.

Total area of the boat hull, or just what's in the water i.e. waterplane
area? You could use the pounds per inch immersion formula.

http://dan.pfeiffer.net/boat/ratios.htm#lbsin

Submarines, Car Engines, and Displacement
 

On 07 Jan 2004 08:04:48 GMT, (Gould 0738) wrote:

Fascinating. What does the depth indicator say when the sub is surfaced?
Obviously it would not be zero.

That would depend on how far it surfaced. Did it blow all ballast or is
it just barely surfaced?

Steve


It can't blow enough ballast to put the keel on the surface. My point is merely
that if the depth is measured between the surface and the keel, (and I have no
reason to doubt that it is) there could never be a "zero" reading.

Think about it - "zero" is the bottom of the boat. If your boat draws
18 inches of water, then your keel is 18 inches below the surface and
thus that is "zero".

Zero is a fictional number anyway and can mean anything.

Later,

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

St. Pete, 12 Lb. Test

Submarines, Car Engines, and Displacement
 

On Wed, 07 Jan 2004 00:20:29 -0500, Wayne.B
wrote:

On 07 Jan 2004 02:52:36 GMT, (Gould 0738) wrote:

Fascinating. What does the depth indicator say when the sub is surfaced?
Obviously it would not be zero.

We used to see subs on the surface all the time in eastern Long Island
Sound (sub base at Groton, CT). Only the conning tower and maybe 6
to 8 feet of hull is exposed at most when they are surfaced.
Estimating that the conning tower is submerged by 10 feet at periscope
depth, the height of the tower at 20 feet, plus 8 feet of hull - that
would put you about 38 feet above the periscope depth reading.

If you motor up the Thames River from New London, CT, you can actually
see partially assembled cross sections of subs on dry land. They look
incredibly big, even from a distance. And you really don't want to
take a lot of pictures or try to get closer. :-)

It's even more fun out at The Race when those subs go by - it's quite
a ride when they sneak up on you. I damn near got tossed out of my
Ranger once fishing the rip halfway between Race Rock and LI.

Damn subs. :)

Later,

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

St. Pete, 12 Lb. Test

Submarines, Car Engines, and Displacement
 

"Gould 0738" wrote in message
...
Fascinating. What does the depth indicator say when the sub is surfaced?
Obviously it would not be zero.

That would depend on how far it surfaced. Did it blow all ballast or is
it just barely surfaced?

Steve


It can't blow enough ballast to put the keel on the surface. My point is
merely
that if the depth is measured between the surface and the keel, (and I
have no
reason to doubt that it is) there could never be a "zero" reading.

There is never a "Zero" reading, when on the surface it
is mid to high 30's depending on the type of sub. Also
for safety sake we never surface a little bit, when we
surface all ballast is blown.

Terry

Submarines, Car Engines, and Displacement
 

There is never a "Zero" reading, when on the surface it
is mid to high 30's depending on the type of sub. Also
for safety sake we never surface a little bit, when we
surface all ballast is blown.

Terry

Thanks!

Submarines, Car Engines, and Displacement
 

"del cecchi" wrote

Ahhh yes, there are the creative ideas I was thinking
must be out there.

Thanks to everyone that responded to these questions.

Submarines, Car Engines, and Displacemen
 

"K Smith"

From your thread title I think you want the "volume" of the hull below
the water line??? not the area??? Also your question seems to suggest
"while it's in the water"?? you want to work this out without pulling
the boat out??


Sorry, not worded clearly on my part.

I'm looking for the area. Reason is just for curiosity. Reason I want the
area
is to calculate the pressure per square inch. Example: Boat is 4000 lbs,
area
where it touches the water is X. So approximate pounds/square inch is Y.

No, I don't need to do this IN the water. What I was trying to say is that
I only want the area that TOUCHES the water. The remaining area of the
hull would not be "supporting" the boat while in the water.

It's just a winter month curiosity exercise.

Thanks.

Submarines, Car Engines, and Displacement
 

Again, thanks for all the answers.

Submarines, Car Engines, and Displacement
 

Gould 0738 wrote:

I don't dispute that- ergo the disclaimer.
But if the depth is measured from the keel and there is a depth indicator on
the sub it will never read zero. Is that somehow incorrect? That was why I
postulated *if* a depth guage read zero at the surface the reading would have
to be from the normally ballasted waterline. Since it apparently does not read
zero, that theory doesn't fly. Freely admitted.

It has never been part of submarine law that it must read zero on the
surface. Why should it?

The depth to keel is also an indication of freeboard. A submarine, after
surfacing, will use a low pressure blower to push the last bit of water
from the ballast tanks in order to increase the freeboard. The depth
gauge shows when it is as high as it will go.

Rick

Submarines, Car Engines, and Displacement
 

"Rick" wrote:


On modern gas car engines and when it's cold
outside, is it still better to let them warm up a
bit and how warm (how long) is necessary?

RTFM

I read the f'ing manual. It explains how
to start it in the cold but not a word
about warming it up or idling.

Submarines, Car Engines, and Displacemen
 

"Gary Warner" wrote in message
...
Sorry, not worded clearly on my part.

I'm looking for the area. Reason is just for curiosity. Reason I want
the
area
is to calculate the pressure per square inch. Example: Boat is 4000 lbs,
area
where it touches the water is X. So approximate pounds/square inch is Y.

No, I don't need to do this IN the water. What I was trying to say is
that
I only want the area that TOUCHES the water. The remaining area of the
hull would not be "supporting" the boat while in the water.

It's just a winter month curiosity exercise.

Thanks.



Do not need the wetted area of the boat for those calculations. Just how
far under water is the square inch. And take the average depth of the
location and multiply by the pressure at depth. And the pressure is a
little under 1/2 psi per inch of depth.
Bill

Submarines, Car Engines, and Displacemen
 

K Smith wrote:



This is a mea culpa.

I've made a mistake!! (yes, yes I know; again!!)

If there is anything I can say in mitigation, it's that I did realise
it on my own, get it checked this time:-) & have now tried to belatedly
correct it.


To measure surface area accurately you'll need to measure 1/2 the
bottom of the boat & that part of the sides (if a chine boat) below the
waterline, where ever possible reduce it to oblongs or squares, then
various right triangles when you run out of easy oblongs etc. Add them
all together, double it & that's the total surface area.

In boat design they use a planimeter to run over the lines.

To calculate the "displacement" (volume of the boat below the
waterline) you can actually get a pretty accurate measurement by using
"simpson's formula" even as your question seems to suggest, with the
boat still in the water by;

(i) Boats are usually designed on 10 "sections" i.e. notionally the
boat has 11 transverse stations/bulkheads across it equal distance apart
from the waterline bow. Say a 30 ft WL boat they'd be 3ft apart?? These
stations/bulkheads are not "real", although usually bulkheads are at a
station point, but whatever but you can easily measure with a tape what
the below waterline areas would be, even on a bigger boat.

(ii) You need to measure the "area" of each of those notional
stations/bulkheads, but just that area which is below the waterline.

This is WRONG it's not the "area" it's the perimeter length or
circumference!! Having made this error I carried it on through the rest
of the description.

(again designers with plans drawings etc run around the 1/2 shape X3 div
by 3 to average with a planimeter)

Damn!!! I even correctly described how designers measure the perimeter
length of irregular shapes, but once I had a mindset of "area", well
there ya go, I'm sorry again.

(iii) Once you know the below the waterline only area in sq ft

This should read "Once you know the below the waterline only perimeter
length in inches"

of
each of the boat's 10 notional stations, you multiple each by simpson's
multipliers 1,4,2,4,2,4,2,4,2,4,1 (11 notional below waterline
stations/bulkheads gives 10 equal length sections of the boat)

(iv) Add all the answers together so you now have the sum of functions.

(v) Use simpson's formula to work out the boat or ship's current
displacement per;

2 X 1/3 X sum of functions of 1/2 areas X (inverted scale)sq X the
common interval X 64 = displacement in ponds of salt water, or for fresh
water use 62.2 as the last figure.

This is the formula as used in boat design, so it is a bit more yuk
than you need, all you need is;

(a) 2 is to account for only using 1/2 the below waterline
station/bulkhead area, you can leave it out if you measured the full sq
ft of each area before using his multipliers.

(b) 1/3 is just part of the formula.

(c) Sum of the functions is explained in (iv) above. (but
designers tend to just use 1/2 then multiply by 2 see (a))

(d) Inverted scale squared doesn't bother you because you
can use feet as a direct measure, whereas a designer might be using say
1/2"
to the foot in their drawings. So make sure your notional below the
waterline areas or 1/2 areas if you choose, are in sq ft.

This whole paragraph needs correction because clearly if you have the
sum of functions in inches then you don't need to adjust for scale. So
you just use you answer from (iv)

(e) Common interval is the length in feet of each section,
again say it's waterline length of 30 ft the "common interval" is 3.

(f) At this point the formula should have delivered you the
boat's below the waterline volume in cubic feet, the 64 is just the
weight in pounds of a cubic ft of salt water, or 62.2 for fresh water;
to give you the displacement in lbs (weight of the boat).

The rest looks pretty much OK, so I hope not too many of you have been
working in vain on this:-) Of course I know I know I know nobody even
read it:-) but so what?? it was wrong:-) I can't help but correct it for
the record.

Sincere apologies again.

K


K




Gary

Submarines, Car Engines, and Displacement
 

On 07 Jan 2004 08:04:48 GMT, (Gould 0738) wrote:

Fascinating. What does the depth indicator say when the sub is surfaced?
Obviously it would not be zero.

That would depend on how far it surfaced. Did it blow all ballast or is
it just barely surfaced?

Steve

If you do an emergency blow from test depth, the forward third of the boat will
come completely out of the water when the boat reaches the surface. For those
few seconds I think that would be a 'zero' reading.

JJ


It can't blow enough ballast to put the keel on the surface. My point is merely
that if the depth is measured between the surface and the keel, (and I have no
reason to doubt that it is) there could never be a "zero" reading.

James Johnson
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Submarines, Car Engines, and Displacement
 

On Sat, 10 Jan 2004 01:44:51 +0000, James Johnson wrote:


If you do an emergency blow from test depth, the forward third of the boat
will come completely out of the water when the boat reaches the surface.
For those few seconds I think that would be a 'zero' reading.

I think we have all seen pictures of that, quite impressive. I've always
wondered what it would be like inside at the time. It must be a rather
rough ride?

Submarines, Car Engines, and Displacement
 

yes, a sub can read zero ! talking to my dad who worked on subs, actually
the gauge can be re-calibrated thus zero can be read. at any point they
wish, when the bottom of the hull is still 20feet below the surface.
Most of you, do not even know, nuclear bombs are also placed in special
torpedoes, of which it would not take more than two to take out Cuba !!!

"James Johnson" wrote in message
...
On 07 Jan 2004 08:04:48 GMT, (Gould 0738) wrote:

Fascinating. What does the depth indicator say when the sub is
surfaced?
Obviously it would not be zero.

That would depend on how far it surfaced. Did it blow all ballast or is
it just barely surfaced?

Steve

If you do an emergency blow from test depth, the forward third of the boat
will
come completely out of the water when the boat reaches the surface. For
those
few seconds I think that would be a 'zero' reading.

JJ


It can't blow enough ballast to put the keel on the surface. My point is
merely
that if the depth is measured between the surface and the keel, (and I
have no
reason to doubt that it is) there could never be a "zero" reading.

James Johnson
remove the "dot" from after sail in email address to reply

Submarines, Car Engines, and Displacement
 

"Joseph Stachyra" wrote
(snip )
Most of you, do not even know, nuclear bombs are also placed in special
torpedoes, of which it would not take more than two to take out Cuba !!!

Please, don't even think that about Cuba. It is a beautiful country and I
am going boating there, in February, for my annual winter vaction!!!!

Jim Carter
"The Boat"
Bayfield

Submarines, Car Engines, and Displacement
 

Jim Carter wrote:

"Joseph Stachyra" wrote
(snip )
Most of you, do not even know, nuclear bombs are also placed in special
torpedoes, of which it would not take more than two to take out Cuba !!!

Please, don't even think that about Cuba. It is a beautiful country and I
am going boating there, in February, for my annual winter vaction!!!!

Jim Carter
"The Boat"
Bayfield


Good grief. Cuba. Why are we still at war with Cuba? If there is a
dumber American foreign policy than what we've done with Cuba for the
last half-century, I'm unaware of it.

Even today, Bush is kissing the ass of the PRC and horrific
dictatorships all over the world, but is kicking Cuba in the ass.

Ker-ripes.







--
Email sent to is never read.

Submarines, Car Engines, and Displacement
 

On Sat, 10 Jan 2004 16:03:06 GMT, "Joseph Stachyra"
wrote:

yes, a sub can read zero ! talking to my dad who worked on subs, actually
the gauge can be re-calibrated thus zero can be read. at any point they
wish, when the bottom of the hull is still 20feet below the surface.
Most of you, do not even know, nuclear bombs are also placed in special
torpedoes, of which it would not take more than two to take out Cuba !!!

There are also nuclear bombs on depth charges, of which it would not
take more than one to take out a submarine.:)

Steve

Submarines, Car Engines, and Displacement
 

On Sat, 10 Jan 2004 11:26:24 -0500, Harry Krause
wrote:

Jim Carter wrote:

"Joseph Stachyra" wrote
(snip )
Most of you, do not even know, nuclear bombs are also placed in special
torpedoes, of which it would not take more than two to take out Cuba !!!

Please, don't even think that about Cuba. It is a beautiful country and I
am going boating there, in February, for my annual winter vaction!!!!

Jim Carter
"The Boat"
Bayfield


Good grief. Cuba. Why are we still at war with Cuba? If there is a
dumber American foreign policy than what we've done with Cuba for the
last half-century, I'm unaware of it.

We're at war with Cuba? That I was unaware of.

Even today, Bush is kissing the ass of the PRC and horrific
dictatorships all over the world, but is kicking Cuba in the ass.

We just need to strip the Cuban exiles in this country of their right to
vote and then we can all visit Cuba and spend our money there legally.

Steve

Submarines, Car Engines, and Displacement
 

Steven Shelikoff wrote:
On Sat, 10 Jan 2004 11:26:24 -0500, Harry Krause
wrote:

Jim Carter wrote:

"Joseph Stachyra" wrote
(snip )
Most of you, do not even know, nuclear bombs are also placed in special
torpedoes, of which it would not take more than two to take out Cuba !!!

Please, don't even think that about Cuba. It is a beautiful country and I
am going boating there, in February, for my annual winter vaction!!!!

Jim Carter
"The Boat"
Bayfield


Good grief. Cuba. Why are we still at war with Cuba? If there is a
dumber American foreign policy than what we've done with Cuba for the
last half-century, I'm unaware of it.

We're at war with Cuba? That I was unaware of.

Don't be so literal, Steve. It doesn't become you.


Even today, Bush is kissing the ass of the PRC and horrific
dictatorships all over the world, but is kicking Cuba in the ass.

We just need to strip the Cuban exiles in this country of their right to
vote and then we can all visit Cuba and spend our money there legally.

Steve

Well, we do need to ensure that after Castro, the exiles don't go back
and try to assert some "rights" they think they have.

--
Email sent to is never read.

Submarines, Car Engines, and Displacement
 

On Fri, 09 Jan 2004 23:01:53 -0500, thunder wrote:

On Sat, 10 Jan 2004 01:44:51 +0000, James Johnson wrote:


If you do an emergency blow from test depth, the forward third of the boat
will come completely out of the water when the boat reaches the surface.
For those few seconds I think that would be a 'zero' reading.

I think we have all seen pictures of that, quite impressive. I've always
wondered what it would be like inside at the time. It must be a rather

Everything is rattling, shaking and vibrating on the way up. When you break the
surface it suddenly gets a lot quieter, and the fall back down is surprisingly
gentle compared to the ride up.

JJ

rough ride?

James Johnson
remove the "dot" from after sail in email address to reply

Submarines, Car Engines, and Displacement
 

On Sat, 10 Jan 2004 16:21:30 GMT, "Jim Carter" wrote:


"Joseph Stachyra" wrote
(snip )
Most of you, do not even know, nuclear bombs are also placed in special
torpedoes, of which it would not take more than two to take out Cuba !!!

I don't think the Mark45 has been deployed in decades. They were not very
practical, for even at maximum range and the boat pointed either directly
towards or directly away from the target there was a surprisingly large chance
that you would not survive the shock waves. Cruise missiles made them obsolete.

JJ

Please, don't even think that about Cuba. It is a beautiful country and I
am going boating there, in February, for my annual winter vaction!!!!

Jim Carter
"The Boat"
Bayfield


James Johnson
remove the "dot" from after sail in email address to reply

Submarines, Car Engines, and Displacement
 

snip

Well, we do need to ensure that after Castro, the exiles don't go back
and try to assert some "rights" they think they have.

I heard from someone who had been to Cuba often that the Cubans aren't
going to have somebody in power who fled to the US and missed the
"Hard Times" under Castro. Maybe it was on one of the boat groups,
now that I think about it.
Mark E. Williams