Squall torpedo

[Spitfiremk9]

Whoops there goes another Super Carrier (steering gear & screws) !

http://www.diodon349.com/Kursk-Memorial/storm_over_the_squall.htm

[Keith Willshaw]

"Spitfiremk9" > wrote in message
...
> Whoops there goes another Super Carrier (steering gear & screws) !
>
> http://www.diodon349.com/Kursk-Memorial/storm_over_the_squall.htm

Stop being silly

The Skhval is a short range straight runner that does NOT
home in on the steering gear or screws. The Russian
torpedo that IS dangerous in this respect is the large
Type 53-65 passive wake homing torpedo,

Keith

[Nemo l'ancien]

>
>
Silly for sure. How that super-fast torpedo would be able to detect a
target? With a radar, perhaps? LOL!!!!

[D]

----------
In article >,
(Spitfiremk9) wrote:

> Whoops there goes another Super Carrier (steering gear & screws) !
>
> http://www.diodon349.com/Kursk-Memorial/storm_over_the_squall.htm

Both you and the website author are being goofy.

The site clearly states that this is an _anti-submarine_ torpedo.

In addition, the website is wrong about this being the cause for the sinking
of the Kursk. The Russians have concluded that it was actually an older,
conventional torpedo that probably caused the loss.




D

[Eunometic]

"Keith Willshaw" > wrote in message >...
> "Spitfiremk9" > wrote in message
> ...
> > Whoops there goes another Super Carrier (steering gear & screws) !
> >
> > http://www.diodon349.com/Kursk-Memorial/storm_over_the_squall.htm
>
> Stop being silly
>
> The Skhval is a short range straight runner that does NOT
> home in on the steering gear or screws. The Russian
> torpedo that IS dangerous in this respect is the large
> Type 53-65 passive wake homing torpedo,
>
> Keith

I doubt the Russians would produce a completely impracticable weapon.
Almost certainly a modest degree of directional control (perhaps turn
rates of 1 degree per second) is possible if only to keep the missile
on course, homing guidence at full speed might be difficult due to
the gas cavity and rocket motor interfering with both passive and
active sonar but that wouldn't prevent the missile being equiped with
an inertial guidence system able to take the missile to within close
range of the target where it either slows down for a 'look' using
conventional passive or active sonar or it detonates a large (possibly
nuclear) warhead. Even a cheap inertial guidence system would have
drift rates of at most 20 meters per minute; given its speed of well
over 300km/h or 5km/minute so an attack on targets 25 km away would
place the missile within 100 meters of the 'enemy carrier' or 'sub'.

Even attacks using WW2 shoot and forget collision course type aiming
with spreads of torpedos would have a high degree of success given the
enormous speed of the missile preventing evasive manouvers.

[Keith Willshaw]

"Eunometic" > wrote in message
m...
> "Keith Willshaw" > wrote in message
> >...
>> "Spitfiremk9" > wrote in message
>> ...
>> > Whoops there goes another Super Carrier (steering gear & screws) !
>> >
>> > http://www.diodon349.com/Kursk-Memorial/storm_over_the_squall.htm
>>
>> Stop being silly
>>
>> The Skhval is a short range straight runner that does NOT
>> home in on the steering gear or screws. The Russian
>> torpedo that IS dangerous in this respect is the large
>> Type 53-65 passive wake homing torpedo,
>>
>> Keith
>
> I doubt the Russians would produce a completely impracticable weapon.

Its a Hail Mary Weapon intended to be fired at a vessel that has
a lock on you and is about to kill you. At best it might actually hit
the enemy but there's a good chance it'll evade and in doing so
break the lock.


> Almost certainly a modest degree of directional control (perhaps turn
> rates of 1 degree per second) is possible if only to keep the missile
> on course, homing guidence at full speed might be difficult due to
> the gas cavity and rocket motor interfering with both passive and
> active sonar but that wouldn't prevent the missile being equiped with
> an inertial guidence system able to take the missile to within close
> range of the target where it either slows down for a 'look' using
> conventional passive or active sonar or it detonates a large (possibly
> nuclear) warhead. Even a cheap inertial guidence system would have
> drift rates of at most 20 meters per minute; given its speed of well
> over 300km/h or 5km/minute so an attack on targets 25 km away would
> place the missile within 100 meters of the 'enemy carrier' or 'sub'.
>

Trouble is we know the weapon has no sucuh guidance system
and that its range is nothing like 25 km. Russia began marketing
the conventionally armed version of the Shkval at the IDEX 99
exhibition in Abu Dhabi in early 1999. The firisng system
sets the speed, distance and vector and feeds the data to the
missile's automatic pilot. The missile is fired, achieves its
optimum depth and switches on its engines. The missile
does not have a homing warhead

> Even attacks using WW2 shoot and forget collision course type aiming
> with spreads of torpedos would have a high degree of success given the
> enormous speed of the missile preventing evasive manouvers.

If it were not for the fact that its range is less than 8000 yards

Keith

[Merlin]

"U.S. intelligence has received several indications that the Russians
were working on an ADVANCED, MUCH LONGER RANGE SHKVAL . Russia's
Itar-Tass news agency reported in February 1998, for instance, that
tests of a "modernized" Shkval were scheduled by Russia's Pacific Fleet
for that spring."

FEBRUARY 1998 - THAT'S SIX YEARS AGO ! PLENTY OF TIME FOR EXTRA R & D ?


Other informed sources claim that the missile is in fact an offensive
weapon designed to destroy entire AIRCRAFT CARRIER battle groups with a
higher-yield nuclear warhead. During a nuclear war, it could even be
directed at a port or coastal land target.

"As there are NO KNOWN COUNTERMEASURES TO SUCH A WEAPON," states
Miller's 1995 Jane's article, "its deployment could have a significant
effect on future maritime operations, both surface and subsurface, and
could put Western naval forces at a considerable disadvantage."

Guidance at speed had been unavailable on the original model of the
torpedo due to the difficulty sonar has in penetrating the surrounding
gas envelope and what experts call "self-noise," but the Russians are
said to have now added a homing capability to the deadly device.
Reportedly, the improved homing version runs out at very high speed,
then slows to search for its target. If this is true, the new version
troubles top U.S. Navy brass, who would like to know as much as
possible about the advanced Shkval before it finds its way to places
such as China and Iran.

Gundarov also wrote that the Kursk was retrofitted during the same
period with a potentially problematic torpedo-launching system against
the wishes of many high-ranking Russian navy officials who considered
it to be "complicated and dangerous." The existing high-cost
silver-zinc battery and propeller system used for years to send the
Shkval out to a safe distance and orient it toward its target before
its rocket engine ignites was replaced. The new system employs a
higher-risk technology that uses a gas stream to propel the torpedo out
the tube. When the weapon is triggered, liquid fuel is burned
generating pressurized gas that shoots the Shkval out the launch tube.



D wrote:
> ----------
> In article >,
> (Spitfiremk9) wrote:
>
> > Whoops there goes another Super Carrier (steering gear & screws) !
> >
> > http://www.diodon349.com/Kursk-Memorial/storm_over_the_squall.htm
>
> Both you and the website author are being goofy.
>
> The site clearly states that this is an _anti-submarine_ torpedo.
>
> In addition, the website is wrong about this being the cause for the
sinking
> of the Kursk. The Russians have concluded that it was actually an
older,
> conventional torpedo that probably caused the loss.
>
>
>
>
> D

[FatKat]

How big is Shkval, anyway? Does it fire out of conventional tubes? It
just occurred to me that a system like shkval might be great as a
booster for smaller torp - sort of a submerged version of SUBROC, with
a mini torp deployed near a point pre-set by the firing sub.

[Eunometic]

"Keith Willshaw" > wrote in message >...
> "Eunometic" > wrote in message
> m...
> > "Keith Willshaw" > wrote in message
> > >...
> >> "Spitfiremk9" > wrote in message
> >> ...
> >> > Whoops there goes another Super Carrier (steering gear & screws) !
> >> >
> >> > http://www.diodon349.com/Kursk-Memorial/storm_over_the_squall.htm
> >>
> >> Stop being silly
> >>
> >> The Skhval is a short range straight runner that does NOT
> >> home in on the steering gear or screws. The Russian
> >> torpedo that IS dangerous in this respect is the large
> >> Type 53-65 passive wake homing torpedo,
> >>
> >> Keith
> >
> > I doubt the Russians would produce a completely impracticable weapon.
>
> Its a Hail Mary Weapon intended to be fired at a vessel that has
> a lock on you and is about to kill you. At best it might actually hit
> the enemy but there's a good chance it'll evade and in doing so
> break the lock.
>
>
> > Almost certainly a modest degree of directional control (perhaps turn
> > rates of 1 degree per second) is possible if only to keep the missile
> > on course, homing guidence at full speed might be difficult due to
> > the gas cavity and rocket motor interfering with both passive and
> > active sonar but that wouldn't prevent the missile being equiped with
> > an inertial guidence system able to take the missile to within close
> > range of the target where it either slows down for a 'look' using
> > conventional passive or active sonar or it detonates a large (possibly
> > nuclear) warhead. Even a cheap inertial guidence system would have
> > drift rates of at most 20 meters per minute; given its speed of well
> > over 300km/h or 5km/minute so an attack on targets 25 km away would
> > place the missile within 100 meters of the 'enemy carrier' or 'sub'.
> >
>
> Trouble is we know the weapon has no sucuh guidance system
> and that its range is nothing like 25 km. Russia began marketing
> the conventionally armed version of the Shkval at the IDEX 99
> exhibition in Abu Dhabi in early 1999. The firing system
> sets the speed, distance and vector and feeds the data to the
> missile's automatic pilot. The missile is fired, achieves its
> optimum depth and switches on its engines. The missile
> does not have a homing warhead
>
> > Even attacks using WW2 shoot and forget collision course type aiming
> > with spreads of torpedos would have a high degree of success given the
> > enormous speed of the missile preventing evasive manouvers.
>
> If it were not for the fact that its range is less than 8000 yards

The site refered to at the begining of the thread refers to a switch
from solid propellant to liquid propulsion. This would appear to give
several advantages.

1 Higher specific impulse therfore speed and range.
2 The rocket-torpedo can be ejected from its own tube: manouever and
aligne itself towards the target at low speed by varying its thrust
and then accelerate at high speed rather than relying on a propellor
based system to achieve initial alignment.
3 After having intercepted its target at high speed it can slow down
for a 'look' using its terminal homing system and then re-alinge and
re-accelerate.

I also can see why the system can't use a trailing wire command
guidence systemn as conventional torpedos and missiles use. It may
have uses as a torpedo intercept system.



>
> Keith

[Keith Willshaw]

"Eunometic" > wrote in message
om...
> "Keith Willshaw" > wrote in message
> news:<colm61$gr5$1
>
> The site refered to at the begining of the thread refers to a switch
> from solid propellant to liquid propulsion. This would appear to give
> several advantages.
>
> 1 Higher specific impulse therfore speed and range.

And considerable increase in risk, liquid propellants in
the torpedo room - shudders !

> 2 The rocket-torpedo can be ejected from its own tube: manouever and
> aligne itself towards the target at low speed by varying its thrust
> and then accelerate at high speed rather than relying on a propellor
> based system to achieve initial alignment.

Throttlable rocket engines are considerably more complex
and the risk to the launcher just went up again.

> 3 After having intercepted its target at high speed it can slow down
> for a 'look' using its terminal homing system and then re-alinge and
> re-accelerate.
>

Not without turning off the gas generator for the supercavitation

> I also can see why the system can't use a trailing wire command
> guidence systemn as conventional torpedos and missiles use. It may
> have uses as a torpedo intercept system.
>

That wire would trail behind the torpedo where the rocket exhaust is

Oops

Keith

[Spitfiremk9]

You MAY be correct about the old torpedo. There was a British TV
programme that pointed with good evidence to this fact.

However - I think a point is being missed here ?

Super-Cavitation Technology ?

What can be applied to a torpedo can equally applied to a submarine.

The Russians have retired their 'Golden Bullet' 45 knot Alpha Class Submarines.

A 'Super-Cavitating' submarine that uses this ability as a 'sprint' ?

Interesting no ?

Merlin



"D" > wrote in message >...
> ----------
> In article >,
> (Spitfiremk9) wrote:
>
> > Whoops there goes another Super Carrier (steering gear & screws) !
> >
> > http://www.diodon349.com/Kursk-Memorial/storm_over_the_squall.htm
>
> Both you and the website author are being goofy.
>
> The site clearly states that this is an _anti-submarine_ torpedo.
>
> In addition, the website is wrong about this being the cause for the sinking
> of the Kursk. The Russians have concluded that it was actually an older,
> conventional torpedo that probably caused the loss.
>
>
>
>
> D

[George Ruch]

(Spitfiremk9) wrote:

>You MAY be correct about the old torpedo. There was a British TV
>programme that pointed with good evidence to this fact.
>
>However - I think a point is being missed here ?
>
>Super-Cavitation Technology ?
>
>What can be applied to a torpedo can equally applied to a submarine.
[...]
>A 'Super-Cavitating' submarine that uses this ability as a 'sprint' ?

Which would completely defeat the any modern submarine's greatest advantage
- stealth. You might as well paint a huge, luminescent, noisy bulls' eye
on it.

| George Ruch
| "Is there life in Clovis after Clovis Man?"

[Keith Willshaw]

"Spitfiremk9" > wrote in message
. ..
> You MAY be correct about the old torpedo. There was a British TV
> programme that pointed with good evidence to this fact.
>
> However - I think a point is being missed here ?
>
> Super-Cavitation Technology ?
>
> What can be applied to a torpedo can equally applied to a submarine.
>

Not easily, rocket propelled submarines would seem
a non trivial development.

> The Russians have retired their 'Golden Bullet' 45 knot Alpha Class
> Submarines.
>

Given their design , liquid metal cooled rectors etc that
was very wide of them

> A 'Super-Cavitating' submarine that uses this ability as a 'sprint' ?
>

And makes so much noise that every SOSUS station on the
planet hears them

> Interesting no ?
>

No

Keith

[agh]

"Keith Willshaw" > wrote in message
...
> And makes so much noise that every SOSUS station on the
> planet hears them

Is submarine's stealth cruising the only situation the submarine can be
caught in? Let's say it's already located and has a torpedo coming at it. Or
some situation develops where it has to travel very fast to some place, e.g.
some rescue operation or something, it doesn't really matter. In those
situations I wouldn't give a **** about some SOSUS tracking my ass but would
be very thankful to the engineers that provided me with this neat feature.

[Keith Willshaw]

"agh" > wrote in message ...
> "Keith Willshaw" > wrote in message
> ...
>> And makes so much noise that every SOSUS station on the
>> planet hears them
>
> Is submarine's stealth cruising the only situation the submarine can be
> caught in? Let's say it's already located and has a torpedo coming at it.
> Or
> some situation develops where it has to travel very fast to some place,
> e.g.
> some rescue operation or something, it doesn't really matter. In those
> situations I wouldn't give a **** about some SOSUS tracking my ass but
> would
> be very thankful to the engineers that provided me with this neat feature.
>
>

The question is how much are you prepared to give up
to get it ?

Supercavitation requires a large gas generating capacity
and humongous amount of thrust. To achieve this the
Shkval has a honking great solid fuel rocket that takes
up most of its interior space and has a range of less than
6 miles.

Push your submarine 5 miles downrange this way and you'll
delay the helicopter by perhaps 3 minutes while providing him
with a confirmation of your presence and a precise location

Personally I'd prefer a decent decoy.

Keith

[agh]

"Keith Willshaw" > wrote in message
...
> Supercavitation requires a large gas generating capacity
> and humongous amount of thrust. To achieve this the
> Shkval has a honking great solid fuel rocket that takes
> up most of its interior space and has a range of less than
> 6 miles.

Yes, I see your point. You're absolutely right. It is quite impractical (or,
better, impossible) with today's technology, but it might prove to be an
interesting concept in future.

[[email protected]]

On Fri, 3 Dec 2004 14:16:52 +0100, "agh" > wrote:

>"Keith Willshaw" > wrote in message
...
>> Supercavitation requires a large gas generating capacity
>> and humongous amount of thrust. To achieve this the
>> Shkval has a honking great solid fuel rocket that takes
>> up most of its interior space and has a range of less than
>> 6 miles.
>
>Yes, I see your point. You're absolutely right. It is quite impractical (or,
>better, impossible) with today's technology, but it might prove to be an
>interesting concept in future.

I dunno. ASW is a cat and mouse game. If the mouse wears a bell it
makes the cat's job easier. This has been true since the beginning
and I doubt it will ever change.

Another thing to consider is that which can be done on a small scale
(a torpedo weighing a ton) may not be possible on a large scale (a
submarine weighing thousands of tons). I suspect the ride through
this "bubble" is probably not very smooth and that will cause it's own
set of problems with submarine systems.

And if the amount of propellant to do this for a torpedo poses safety
risks for the sub, consider the tankage that would be required to
carry sufficient propellant for the whole sub. If solid propellant
were used it would be a "one time use" system, and that means you are
sacrificing other things (money, space, sensor capacity, etc.) to get
away once. With these other systems you might evade detection all
together or escape many times.

At the end of the day the weapon will probably give U.S. forces some
pause, but whether or not is it practical remains to be seen.

Bill Kambic

[Gord Beaman]

"Keith Willshaw" > wrote:

>
>"Eunometic" > wrote in message
om...
>> "Keith Willshaw" > wrote in message
>> news:<colm61$gr5$1
>>
>> The site refered to at the begining of the thread refers to a switch
>> from solid propellant to liquid propulsion. This would appear to give
>> several advantages.
>>
>> 1 Higher specific impulse therfore speed and range.
>
>And considerable increase in risk, liquid propellants in
>the torpedo room - shudders !
>
>> 2 The rocket-torpedo can be ejected from its own tube: manouever and
>> aligne itself towards the target at low speed by varying its thrust
>> and then accelerate at high speed rather than relying on a propellor
>> based system to achieve initial alignment.
>
>Throttlable rocket engines are considerably more complex
>and the risk to the launcher just went up again.
>
>> 3 After having intercepted its target at high speed it can slow down
>> for a 'look' using its terminal homing system and then re-alinge and
>> re-accelerate.
>>
>
>Not without turning off the gas generator for the supercavitation
>
>> I also can see why the system can't use a trailing wire command
>> guidence systemn as conventional torpedos and missiles use. It may
>> have uses as a torpedo intercept system.
>>
>
>That wire would trail behind the torpedo where the rocket exhaust is
>
>Oops
>
>Keith
>
Do torps really use trailing wire guidance now?...they sure
didn't when I was involved in ASW between 1951 and 77. Matter of
fact I never heard of that before, (although some 'missiles' do).
--

-Gord.
(use gordon in email)

[Paul J. Adam]

In message >, Eunometic
> writes
>I doubt the Russians would produce a completely impracticable weapon.

However, not all their concepts have proved effective when tested, and
many have performed poorly when exported in a reduced-specification
version

>Almost certainly a modest degree of directional control (perhaps turn
>rates of 1 degree per second) is possible

How? It's in a supercavitating bubble. Depth keeping and an
approximately straight line is the best it will manage without dumping
the bubble.

>if only to keep the missile
>on course, homing guidence at full speed might be difficult due to
>the gas cavity

Try "impossible". That supercavitation effect blinds any possible
sensor, plus the location for the sensor array is taken up by the gas
bleed.

Similar set of problems to polyox injection, except supercavitation at
least gives a lot more speed.

>and rocket motor interfering with both passive and
>active sonar but that wouldn't prevent the missile being equiped with
>an inertial guidence system able to take the missile to within close
>range of the target where it either slows down for a 'look' using
>conventional passive or active sonar or it detonates a large (possibly
>nuclear) warhead.

Shkval was designed as a reactive weapon to throw a packet of instant
sunshine in the general direction of an enemy who had revealed himself
by firing. It's now being marketed as a conventional weapon intended
to... well.. go really fast.

>Even a cheap inertial guidence system would have
>drift rates of at most 20 meters per minute; given its speed of well
>over 300km/h or 5km/minute so an attack on targets 25 km away would
>place the missile within 100 meters of the 'enemy carrier' or 'sub'.

Plus five minutes of movement by the carrier or submarine, who has heard
this weapon coming. (Shkval's range is typically cited as only around
6,000 yards, for reference)

>Even attacks using WW2 shoot and forget collision course type aiming
>with spreads of torpedos would have a high degree of success given the
>enormous speed of the missile preventing evasive manouvers.

In all this, you assume perfect targeting by the submarine, of course.
How precisely can you judge bearing, range, course and speed of a
submarine from 25 kilometres out?

--
He thinks too much: such men are dangerous.
Julius Caesar I:2

Paul J. Adam MainBox<at>jrwlynch[dot]demon{dot}co(.)uk

[Keith Willshaw]

"Gord Beaman" > wrote in message
...
> "Keith Willshaw" > wrote:
>

> Do torps really use trailing wire guidance now?...

Yep

> they sure
> didn't when I was involved in ASW between 1951 and 77. Matter of
> fact I never heard of that before, (although some 'missiles' do).
> --

http://www.fas.org/man/dod-101/sys/ship/weaps/mk-48.htm
http://americanhistory.si.edu/subs/weapons/armament/torpedoes/
http://www.sfu.ca/casr/101-navtorp1.htm
http://www.naval-technology.com/projects/scorpene/scorpene3.html

and to keep Paul Adam happy

Spearfish Spearfish Rah Rah Rah

http://www.naval-technology.com/projects/vanguard/

Keith

[Thomas Schoene]

Gord Beaman wrote:

> Do torps really use trailing wire guidance now?...they sure
> didn't when I was involved in ASW between 1951 and 77. Matter of
> fact I never heard of that before, (although some 'missiles' do).

Air-launched lightweight torpedoes don't, with one notable exception -- the
Swedish 400mm series (Tp 42, 43, and 46; no relation to US designations).

Heavyweight submarine-launched torpedoes gernerally do. There are
exceptions, of course, but a modern heavyweight is more likely than not to
have wire guidance.

--
Tom Schoene Replace "invalid" with "net" to e-mail
"Our country, right or wrong. When right, to be kept right, when
wrong to be put right." - Senator Carl Schurz, 1872

[Gord Beaman]

"Thomas Schoene" > wrote:

>Gord Beaman wrote:
>
>> Do torps really use trailing wire guidance now?...they sure
>> didn't when I was involved in ASW between 1951 and 77. Matter of
>> fact I never heard of that before, (although some 'missiles' do).
>
>Air-launched lightweight torpedoes don't, with one notable exception -- the
>Swedish 400mm series (Tp 42, 43, and 46; no relation to US designations).
>
>Heavyweight submarine-launched torpedoes gernerally do. There are
>exceptions, of course, but a modern heavyweight is more likely than not to
>have wire guidance.

Thanks Tom, Being familiar with air launched units only I hadn't
heard of this method much before.

I suppose that the Swedish job must be launched from helos only
right?...
--

-Gord.
(use gordon in email)

[WaltBJ]

Q: How does a solid rocket fuel compare to liquid fuel as far as
specific thrust versus density of loading?
I can see why the two exotic torp oxidizers/monopropellants I am
familiar with, propylene glycol dinitrate and hi-test hydrogen
peroxide, are not 'sub-friendly' but I don't know how either would
compare to say ammonium perchlorate/aluminum/hydrocarbon solid fuel.
Looks like powered duration on Skval is about 90 seconds max.
Launching it will surely give a very noisy sound signature and a fix
if there's more than one searcher close by - on its origin.
If it is used against a formation it looks like there would be a trade
- one sub for one target.
Walt BJ

[Peter Stickney]

In article >,
(WaltBJ) writes:
> Q: How does a solid rocket fuel compare to liquid fuel as far as
> specific thrust versus density of loading?

I depends on the fuel. Specific Impulse is usually higher for a
liquid, but, especially with a small system, a chunk of that gets
eaten up by hte weight and volume of the tanks, pumps, and
plumbing. (For values of chunk ranging from "A fair bit" to "all").
Fuel density become imortant. Hydrogen can provide an amazing amoutn
of energy, but yyou get about 6 times the kW/l with Kerosene.
One of the early Sparrow III (AIM-7) models used a storable liquid
rocket motor. for that scale of system, it basicall provided the same
performance, in the same volume and weight, as the solids that
replaced it.

> I can see why the two exotic torp oxidizers/monopropellants I am
> familiar with, propylene glycol dinitrate and hi-test hydrogen
> peroxide, are not 'sub-friendly' but I don't know how either would
> compare to say ammonium perchlorate/aluminum/hydrocarbon solid fuel.
> Looks like powered duration on Skval is about 90 seconds max.
> Launching it will surely give a very noisy sound signature and a fix
> if there's more than one searcher close by - on its origin.
> If it is used against a formation it looks like there would be a trade
> - one sub for one target.

Since it's supposedly a nuke, it would be generally considered to have
a Pk of 2.0 - the target, and the shooter.


--
Pete Stickney

Without data, all you have are opinions

[[email protected]]

On 3 Dec 2004 19:38:10 -0800, (WaltBJ) wrote:

>Q: How does a solid rocket fuel compare to liquid fuel as far as
>specific thrust versus density of loading?
>I can see why the two exotic torp oxidizers/monopropellants I am
>familiar with, propylene glycol dinitrate and hi-test hydrogen
>peroxide, are not 'sub-friendly' but I don't know how either would
>compare to say ammonium perchlorate/aluminum/hydrocarbon solid fuel.
>Looks like powered duration on Skval is about 90 seconds max.
>Launching it will surely give a very noisy sound signature and a fix
>if there's more than one searcher close by - on its origin.
>If it is used against a formation it looks like there would be a trade
>- one sub for one target.

In strategic terms that might be a good trade. Tough on the crews,
though.

Bill Kambic

[[email protected]]

In article >, "Keith Willshaw"
> wrote:

>
> The Skhval is a short range straight runner that does NOT
> home in on the steering gear or screws. The Russian
> torpedo that IS dangerous in this respect is the large
> Type 53-65 passive wake homing torpedo,
>
> Keith
>


I find this interesting. What do you mean by "passive wake homing"?

I know what passive guidance means; I'm just not sure what passive
signature a wake-homing Type 53-65 might be guiding on.

Thanks in advance!

[Keith Willshaw]

> wrote in message
...
> In article >, "Keith Willshaw"
> > wrote:
>
>>
>> The Skhval is a short range straight runner that does NOT
>> home in on the steering gear or screws. The Russian
>> torpedo that IS dangerous in this respect is the large
>> Type 53-65 passive wake homing torpedo,
>>
>> Keith
>>
>
>
> I find this interesting. What do you mean by "passive wake homing"?
>
> I know what passive guidance means; I'm just not sure what passive
> signature a wake-homing Type 53-65 might be guiding on.
>

There are a number of techniques for detecting wakes which
include detecting the velocity changes caused by eddying in
the wake and also by IR sensors which detect the temperature
changes.

Whichever method is used the sensor looks upward and the rudder is
set automatically to turn the torpedo through a fixed angle
each time the torpedo crosses the wake of its target.
This enables a torpedo to follow a sinuous track towards the ship
(provided it enters the wake at an acute angle).

It is relative simple for the seeker to determine the boundaries
of the wake, which extends many lengths behind the target.
A wake is difficult to simulate, so countermeasures relying on
seduction are ineffective which is why are Navies showing so
much interest in Hard Kill defenses.

Keith

[[email protected]]

In article >, "Keith Willshaw"
> wrote:

> > wrote in message
> ...
> > In article >, "Keith Willshaw"
> > > wrote:
> >
> >>
> >> The Skhval is a short range straight runner that does NOT
> >> home in on the steering gear or screws. The Russian
> >> torpedo that IS dangerous in this respect is the large
> >> Type 53-65 passive wake homing torpedo,
> >>
> >> Keith
> >>
> >
> >
> > I find this interesting. What do you mean by "passive wake homing"?
> >
> > I know what passive guidance means; I'm just not sure what passive
> > signature a wake-homing Type 53-65 might be guiding on.
> >
>
> There are a number of techniques for detecting wakes which
> include detecting the velocity changes caused by eddying in
> the wake and also by IR sensors which detect the temperature
> changes.
>
> Whichever method is used the sensor looks upward and the rudder is
> set automatically to turn the torpedo through a fixed angle
> each time the torpedo crosses the wake of its target.
> This enables a torpedo to follow a sinuous track towards the ship
> (provided it enters the wake at an acute angle).
>
> It is relative simple for the seeker to determine the boundaries
> of the wake, which extends many lengths behind the target.
> A wake is difficult to simulate, so countermeasures relying on
> seduction are ineffective which is why are Navies showing so
> much interest in Hard Kill defenses.
>
> Keith
>
>
>

Interesting.

I hadn't seen any prior suggestions that torpedoes might conduct wake
homing via IR or eddy detection. This'll give me something to do after
football and a couple of pints.

Thanks.


----
"Eddies in the time stream"
"Is he. What's he doing there?"

[Eunometic]

"Keith Willshaw" > wrote in message >...
> "Eunometic" > wrote in message
> om...
> > "Keith Willshaw" > wrote in message
> > news:<colm61$gr5$1
> >
> > The site refered to at the begining of the thread refers to a switch
> > from solid propellant to liquid propulsion. This would appear to give
> > several advantages.
> >
> > 1 Higher specific impulse therfore speed and range.
>
> And considerable increase in risk, liquid propellants in
> the torpedo room - shudders !

Perhaps.

The Brits and the Ruskies may have screwed up H2O2 but the Swedes
definetly didn't. I don't think a lot of torpedo propulsion systems
are particularly nice to think about except for silver batteries.


> > 2 The rocket-torpedo can be ejected from its own tube: manouever and
> > aligne itself towards the target at low speed by varying its thrust
> > and then accelerate at high speed rather than relying on a propellor
> > based system to achieve initial alignment.
>
> Throttlable rocket engines are considerably more complex
> and the risk to the launcher just went up again.

Once the move to liquid propellants has occured then throttling the
engine is relatively trivial. Hybrid liquid solid systems where the
relatively congeniel fuel is sprayed into a chamber lined with an
solid and stabalised oxidiser are a solution here.


> > 3 After having intercepted its target at high speed it can slow down
> > for a 'look' using its terminal homing system and then re-alinge and
> > re-accelerate.
> >
>
> Not without turning off the gas generator for the supercavitation

And then restarting it at the same time it restarts its rocket motor.

I suspect a ballistic launch out of the water close to the ship with
infra-red or radar terminal homing followed either by skipping back
into the water or a direct attack is even an option.


>
> > I also can see why the system can't use a trailing wire command
> > guidence systemn as conventional torpedos and missiles use. It may
> > have uses as a torpedo intercept system.
> >
>
> That wire would trail behind the torpedo where the rocket exhaust is
>
> Oops

Hellfire, HOT, TOW, Swingfire, Trigat, Milan all manage quite well and
they aren't even sea water cooled.

The Germans even have a small imaging infrared missile called Triton
(based on the air breathing Polyphem) that can be submarine launched
against both land, sea and air targets. It trails a fibre optic cable
and is rocket propelled through the water before exiting.


>
> Keith

[Keith Willshaw]

"Eunometic" > wrote in message
om...
> "Keith Willshaw" > wrote in message
> >...
>> "Eunometic" > wrote in message
>> om...
>> > "Keith Willshaw" > wrote in message
>> > news:<colm61$gr5$1
>> >
>> > The site refered to at the begining of the thread refers to a switch
>> > from solid propellant to liquid propulsion. This would appear to give
>> > several advantages.
>> >
>> > 1 Higher specific impulse therfore speed and range.
>>
>> And considerable increase in risk, liquid propellants in
>> the torpedo room - shudders !
>
> Perhaps.
>
> The Brits and the Ruskies may have screwed up H2O2 but the Swedes
> definetly didn't. I don't think a lot of torpedo propulsion systems
> are particularly nice to think about except for silver batteries.
>


High energy liquid rocket propellants are rather more
hazardous than anything the Swedes used

>
>> > 2 The rocket-torpedo can be ejected from its own tube: manouever and
>> > aligne itself towards the target at low speed by varying its thrust
>> > and then accelerate at high speed rather than relying on a propellor
>> > based system to achieve initial alignment.
>>
>> Throttlable rocket engines are considerably more complex
>> and the risk to the launcher just went up again.
>
> Once the move to liquid propellants has occured then throttling the
> engine is relatively trivial. Hybrid liquid solid systems where the
> relatively congeniel fuel is sprayed into a chamber lined with an
> solid and stabalised oxidiser are a solution here.
>

Doesnt sound capable of being shut off to me.

>
>> > 3 After having intercepted its target at high speed it can slow down
>> > for a 'look' using its terminal homing system and then re-alinge and
>> > re-accelerate.
>> >
>>
>> Not without turning off the gas generator for the supercavitation
>
> And then restarting it at the same time it restarts its rocket motor.
>

A non trivial design task

> I suspect a ballistic launch out of the water close to the ship with
> infra-red or radar terminal homing followed either by skipping back
> into the water or a direct attack is even an option.
>
>
>>
>> > I also can see why the system can't use a trailing wire command
>> > guidence systemn as conventional torpedos and missiles use. It may
>> > have uses as a torpedo intercept system.
>> >
>>
>> That wire would trail behind the torpedo where the rocket exhaust is
>>
>> Oops
>
> Hellfire, HOT, TOW, Swingfire, Trigat, Milan all manage quite well and
> they aren't even sea water cooled.
>
> The Germans even have a small imaging infrared missile called Triton
> (based on the air breathing Polyphem) that can be submarine launched
> against both land, sea and air targets. It trails a fibre optic cable
> and is rocket propelled through the water before exiting.
>


But have MUCH smaller engines

These proposed developments change what is
currently a cheap and simple last chance defensive
weapon into a highy complex and expensive one.

This may be achievable but I rather doubt the Russians
have the cash to do so.

Keith

[Jim Carriere]

Eunometic wrote:
> Hellfire, HOT, TOW, Swingfire, Trigat, Milan all manage quite well and
> they aren't even sea water cooled.

I could be wrong, but I believe no versions of the Hellfire are wire
guided; all versions home in on a laser spot provided by a designator.

TOW, definitely that's what the "W" stands for.

[Dave in San diego]

Jim Carriere > wrote in news:cp5i37$rhl$1
@news.chatlink.com:

> Eunometic wrote:
>> Hellfire, HOT, TOW, Swingfire, Trigat, Milan all manage quite well and
>> they aren't even sea water cooled.
>
> I could be wrong, but I believe no versions of the Hellfire are wire
> guided; all versions home in on a laser spot provided by a designator.
>
> TOW, definitely that's what the "W" stands for.
>

That is correct - HELLFIRE does not use a trailing wire.

TOW = Tube-launched, Optically-tracked, Wire-guided

Dave in San Diego

[Keith Willshaw]

"Jim Carriere" > wrote in message
...
> Eunometic wrote:
>> Hellfire, HOT, TOW, Swingfire, Trigat, Milan all manage quite well and
>> they aren't even sea water cooled.
>
> I could be wrong, but I believe no versions of the Hellfire are wire
> guided; all versions home in on a laser spot provided by a designator.
>

There are both laser and microwave radar seekers available
but no wire guided versions.

Keith

[Paul J. Adam]

In message >, Jim Carriere
> writes
>Eunometic wrote:
>> Hellfire, HOT, TOW, Swingfire, Trigat, Milan all manage quite well and
>> they aren't even sea water cooled.
>
>I could be wrong, but I believe no versions of the Hellfire are wire
>guided; all versions home in on a laser spot provided by a designator.

MR Trigat is a laser beam rider, no wire. LR Trigat is a fire-and-forget
IIR weapon, similar concept to Javelin.

--
He thinks too much: such men are dangerous.
Julius Caesar I:2

Paul J. Adam MainBox<at>jrwlynch[dot]demon{dot}co(.)uk

[John Dallman]

In article >, (Jim
Carriere) wrote:
> Eunometic wrote:
> > Hellfire, HOT, TOW, Swingfire, Trigat, Milan all manage quite well and
> > they aren't even sea water cooled.
> I could be wrong, but I believe no versions of the Hellfire are wire
> guided; all versions home in on a laser spot provided by a designator.
>
> TOW, definitely that's what the "W" stands for.

And TOW's rocket exhaust doesn't come straight out the back, judging by
the pictures I've seen. Two nozzles, one on each side, firing outwards at
an angle of maybe as much as 30 degrees.

---
John Dallman, , HTML mail is treated as probable spam.