Hi Brian.
If her atmosphere is compressed when she
floods her open to the hull interior ballast tanks and the atmosphere is
no longer exactly 1 atm, then she cannot be accurately called 1 atm
which is 14.7 lbs of pressure per square inch.
Some people have said that she is "close" to
one atmosphere. But that is not 1 atm. It does not make sense to call
something a mathematically specific term when it is not. You either are
pregnant or you are not.
You cannot be close to pregnant, you cannot
be a little bit pregnant, you either are or you are not pregnant. Just
like it is either 14.7 lbs of pressure at sea level (1 atm) or it is not.
It would be incorrect to call 15.7 lbs of pressure
1 atm when it is not. That is what you and
others are saying with the Hunley though and it is not correct not only
for the Hunley but for any submarine that does not have an interior
atmosphere of exactly 14.7 lbs of pressure per square inch.
A column of air one inch by one inch wide
extending up into the atmosphere 60 miles presses toward the earth with a
force or weight of 14.7 lbs also known as 1 atmosphere.
Our scientists and mathmaticians calculated 1
atm to be 14.7 lbs. Not 15.7 lbs, not 16.7 lbs nor even less at 13.7 lbs.
Either a submarine's interior atmospheric pressure is 1 atm or 14.7 lbs
per square inch or it is not.
If the Hunley started out at the surface with
hatches open with an interior atmosphere of 14.7 lbs and then trapped
all her air when she submerged, then filled her open to the hull interior
ballast tanks with water which compressed the
rest of the hull's interior atmosphere to a
higher pressure than 14.7 lbs, then the Hunley's atmosphere was no
longer 14.7 lbs and therefore she was no longer a 1 atm sub. As I said in
an earlier e mail, what does "close to 1 atm" mean?
Is that like "a little bit pregnant" or shall
we discuss what the subjective term "reasonable" means? 14.7 lbs of
pressure is NOT subjective. It is a specific mathematical term. 14.7, not
14.8, not 14.6, but 14.7 period.
If the atmosphere of ANY submarine is not
14.7 then they cannot accurately be called a 1 atmosphere submarine
and we need a new term to describe what type of submarine she is. You can
call a pig a giraffe if you want to, but that does not
make it so. I seriously believe we need a new
term in the submarine world to address this discrepancy and I already
suggested it in an earlier posting regarding using 1 atm as a baseline and
testing pressure variables during sea trials and then
catagorizing the sub from a baseline of 1 atm
to whatever her largest pressure variable was. That is accuracy. "Close
to" is not. Show me a sub that has an interior atmosphere that
measures 14.7 lbs of pressure per square inch and I will agree that
is a
1 atm sub. If she has an atmosphere of 14.9
lbs, then she is not 1 atm since 1 atm is 14.7 lbs ONLY. There may be
times she is 1 atm and times she is not, so it would not be correct to
just call her by the term of 1 atm.
It is possible I may be incorrect about the
Hunley being ambient but there is no way she could be 1 atm either with
her tanks compressing her interior hull atmosphere.
I stand by my statement that we need a new
terminology that is mathmatically specific in describing what type a sub
is. If all the submarines that we normally think of as being 1 atm are
actually not always 1 atm, then they cannot with
accuracy
be called 1 atm subs since they are not
always 1 atm. Why name something the specific term of 1 atm that
means a mathematical figure of 14.7 when that thing is not always
14.7?
Kindest Regards,
Bill Akins.
Sent: Friday, June 10, 2005 7:57
PM
Subject: Re: [PSUBS-MAILIST] When
is ambient, ambient and 1 atmosphere, 1 atmosphere?
The Hunley is a 1 ATM
submarine.
Brian Cox