Are they phasing out the S-3 too?

In article ,
wrote:


Yup. And they are also slow and working against the clock

Slow is a relative thing; if one doesn't need to go far, speed is not
a problem. Time is not as much an issue as it once was; modern diesel
boats can stay under for quite a long time. This ain't WWII anymore.

Indeed. But once you go to battery you are working against a finite
limit. In WWII that limit may be been in the 24-36 hour range and by
'62 had progressed to the 96 hour range. I have no idea what it is
today. But that finite limit is still there.

For the AIP subs coming into service now, it's a looong time. See

http://www.chinfo.navy.mil/navpalib/...propulsion.htm

OTOH, I don't know how noisy they might be.

And therein lay an interesting question. :-)

I have some suspicians, but don't have any insider info.

If you are running on batteries then you are very quiet if you stay
slow. If you go fast you drain your batteries AND you cavitate.
Cavitation gives the hunder a detection opportunity.

Like I say, non-nuke subs are a real and substantial threat. They
are not, however, an ultimate threat.


Not an ultimate threat know...but if you are relying on passive
detection and/or low-power active buoys...you're not likely to hit pay
dirt, and it's time to call the HS folks with their 2000 watts of active
pinging power.


--Mike

On Sun, 30 Jan 2005 01:10:11 GMT, Michael Wise wrote:

Not an ultimate threat know...but if you are relying on passive
detection and/or low-power active buoys...you're not likely to hit pay
dirt, and it's time to call the HS folks with their 2000 watts of active
pinging power.

A diesel is going to make a bunch of noise, whether it's breathing air
or running "closed cycle." Turbines make noise even if they are
closed cycle. ANY mechanical power source is going to make noise.
Only on batteries are these subs the Steath Champs we think of. And
then only if they're not cavitating.

And then, yes, a helo in a dip is a very nice sight!!! :-)

Bill Kambic

On Sun, 30 Jan 2005 01:08:59 GMT, Michael Wise wrote:

I seem to recall that they are rather loud when snorting, too.

The term is "snorkeling,"

I guess I'm showing my age, here! :-)

and yes, from a passive acoustical standpoint,
when running their engines, they are just as detectable on the surface
as when snorkeling.

On the surface you get a radar detection opportunity. You get one on
a snorkle mast, too, but it takes a well tuned set with a good
operator to hold one at any range. I was blessed with such a No. 3
back in the Old Days; his record was 28 nm.

Actually, a sub snorkling is MORE detectable passively than when he is
on the surface. Care to go for the extra points and tell us why? ;-)

Bill Kambic

In article ,
wrote:


I seem to recall that they are rather loud when snorting, too.

The term is "snorkeling,"

I guess I'm showing my age, here! :-)


Is that a WWII term?

and yes, from a passive acoustical standpoint,
when running their engines, they are just as detectable on the surface
as when snorkeling.

On the surface you get a radar detection opportunity.

Hence, why I specified from a "passive acoustical" standpoint.


You get one on
a snorkle mast, too, but it takes a well tuned set with a good
operator to hold one at any range. I was blessed with such a No. 3
back in the Old Days; his record was 28 nm.

Actually, a sub snorkling is MORE detectable passively than when he is
on the surface. Care to go for the extra points and tell us why? ;-)


I can't tell you why, because I don't agree with that statement. They
are both easy passive pick-offs with their own weaknesses, however a
running (on engines) surfaced sub makes a lot of both engine and
cavitation noise.


--Mike

In article ,
wrote:

On Sun, 30 Jan 2005 01:10:11 GMT, Michael Wise wrote:

Not an ultimate threat know...but if you are relying on passive
detection and/or low-power active buoys...you're not likely to hit pay
dirt, and it's time to call the HS folks with their 2000 watts of active
pinging power.

A diesel is going to make a bunch of noise, whether it's breathing air
or running "closed cycle." Turbines make noise even if they are
closed cycle. ANY mechanical power source is going to make noise.

Only on batteries are these subs the Steath Champs we think of.


I think most of us here agree with that.


And
then only if they're not cavitating.


Or returning a 2000 watt echo pulse. ; )



And then, yes, a helo in a dip is a very nice sight!!! :-)


And a darn site more effective then a Hoover. ; )



--Mike

wrote:

On Sun, 30 Jan 2005 01:08:59 GMT, Michael Wise wrote:

I seem to recall that they are rather loud when snorting, too.

The term is "snorkeling,"

I guess I'm showing my age, here! :-)

snip

Or if you ever did an exchange tour with the RN. They call it snorting.

Guy

wrote:

On Sat, 29 Jan 2005 23:47:16 GMT, Guy Alcala
wrote:

wrote:

On Sat, 29 Jan 2005 11:57:31 -0500, Andrew C. Toppan
wrote:

On Sat, 29 Jan 2005 11:47:35 -0500, wrote:

Yup. And they are also slow and working against the clock

Slow is a relative thing; if one doesn't need to go far, speed is not
a problem. Time is not as much an issue as it once was; modern diesel
boats can stay under for quite a long time. This ain't WWII anymore.

Indeed. But once you go to battery you are working against a finite
limit. In WWII that limit may be been in the 24-36 hour range and by
'62 had progressed to the 96 hour range. I have no idea what it is
today. But that finite limit is still there.

For the AIP subs coming into service now, it's a looong time. See

http://www.chinfo.navy.mil/navpalib/...propulsion.htm

OTOH, I don't know how noisy they might be.

And therein lay an interesting question. :-)

I have some suspicians, but don't have any insider info.

The unique source of the noise in an AIP boat would appear to be the need to
expel the exhaust byproducts underwater.

Guy

On Sun, 30 Jan 2005 03:07:54 GMT, Michael Wise wrote:

Is that a WWII term?

No, early '70s.


Actually, a sub snorkling is MORE detectable passively than when he is
on the surface. Care to go for the extra points and tell us why? ;-)


I can't tell you why, because I don't agree with that statement.

They don't teach passive accoustic theory anymore?

The reason is that when a sub is surfaced part of the accoustic energy
developed by machinery is radiated into the air. Thus it is not
available to accoustic devices in water. In modern terms, the total
sound energy is reduced.

Submerge the hull and now ALL the sound energy develped is radiated
into the water.

You may not agree, but it's pretty simple physics and what we used to
teach AWANs in basic passive tracking theory.

They
are both easy passive pick-offs with their own weaknesses, however a
running (on engines) surfaced sub makes a lot of both engine and
cavitation noise.

Indeed. But sound energy radiated into the air is no help with
passive tracking.

As to the superiority of the helo over the fixed wing aircraft it very
much depends on the tactical situation. The helo can get up close and
personal, which the fixed wing cannot. The fixed wing has speed that
the helo does not. The large active sonar of the helo is nice, but
DICASS can work, too. Whether or not an SH-60 (or an SH-3, for that
matter) is the better platform is very situation dependant. It has
been my experience (and that of not a few others) that when you mix
them you can turn a sub every which way but loose.

Bill Kambic

On Sun, 30 Jan 2005 03:10:50 GMT, Guy Alcala
wrote:


Or if you ever did an exchange tour with the RN. They call it snorting.

I've exchanged information with RN types, but never had the pleasure
of an exchange tour. Surely would have been nice to have a glass of
wine with dinner or a cold beer after a warm flight!!!!! :-)

Bill Kambic

In article ,
wrote:


Is that a WWII term?

No, early '70s.


Hmmm, well at least starting in the early 80s, they must have changed
the terminology.


Actually, a sub snorkling is MORE detectable passively than when he is
on the surface. Care to go for the extra points and tell us why? ;-)


I can't tell you why, because I don't agree with that statement.

They don't teach passive accoustic theory anymore?

Sure they do.


The reason is that when a sub is surfaced part of the accoustic energy
developed by machinery is radiated into the air. Thus it is not
available to accoustic devices in water. In modern terms, the total
sound energy is reduced.

No argument there. But when its running surfaced, it's also cavitating
much more which makes up the machinery noise reduction.


Submerge the hull and now ALL the sound energy develped is radiated
into the water.

No argument there. The blade cavitation will also be much less.

You may not agree, but it's pretty simple physics and what we used to
teach AWANs in basic passive tracking theory.


I wasn't taught that as an AW, and it doesn't jibe with my real-world
experiences either.



They
are both easy passive pick-offs with their own weaknesses, however a
running (on engines) surfaced sub makes a lot of both engine and
cavitation noise.

Indeed. But sound energy radiated into the air is no help with
passive tracking.


What makes you think the blade cavitation noise from a sub running on
the surface isn't clear and easily electronically identifiable?


As to the superiority of the helo over the fixed wing aircraft it very
much depends on the tactical situation. The helo can get up close and
personal, which the fixed wing cannot. The fixed wing has speed that
the helo does not.

Speed means nothing when ones tactical avionics package cannot be relied
on.



The large active sonar of the helo is nice, but
DICASS can work, too.


I'll stick with the 2000 watts of power.


Whether or not an SH-60 (or an SH-3, for that
matter) is the better platform is very situation dependant.

Obviously.


It has
been my experience (and that of not a few others) that when you mix
them you can turn a sub every which way but loose.



One would hope so, but I have to say I was never impressed with the
S-3's ASW capabilities (the same goes for the Hooky 2....with no offense
to the talented AW's who flew in both). I flew many an ASW exercises
(aboard SH-3H and SH-60F's) in open ocean as well as semi-controlled
(SOAR range) environments, and it always seemed the VS ASW avionics
systems frequently malfunctioned. I never flew any exercise where they
acquired the target first...although I have flown more than a few where
they lost it after being passed on to them.


--Mike