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.

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

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.

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

"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

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!

"Terry Rago" wrote in message news:eKTKb.766800$Tr4.2203780@attbi_s03...
"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

Airplane altimeters read zero only if the airplane is taxying
into the ocean. Or flying deep in Death Valley or the Dead Sea Valley.
Zero isn't necessary for operators of subs or airplanes or anything
else. I can see that depth to keel would be safest, with reference to
depth charts. In aviation we use maps with obstruction and terrain
altitudes on them.
This complete surfacing of subs: Is this due to the neutral
lateral stability at certain waterlines? I read about that somewhere,
some book that referred to the danger of submerging in really rough
seas and the danger of rollover.

Dan

Dan Thomas wrote:

Airplane altimeters read zero only if the airplane is taxying
into the ocean. Or flying deep in Death Valley or the Dead Sea Valley.
Zero isn't necessary for operators of subs or airplanes or anything
else. I can see that depth to keel would be safest, with reference to
depth charts. In aviation we use maps with obstruction and terrain
altitudes on them.

Perhaps you would like to look up QNH and QFE and get back
to us.

Rick

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

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?