Indian Missiles and Munitions Discussion

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Austin
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Re: Indian Missiles and Munitions Discussion

Postby Austin » 17 Nov 2012 15:01

Shorter than Land Variant as it carries smaller booster

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Re: Indian Missiles and Munitions Discussion

Postby NRao » 18 Nov 2012 08:03

The original plan, for an air based Brahmos, was to have a smaller booster (as compared to a land launched one) because:
1) The MKI could not carry the weight of the land launched one,
2) The air launched one did not need a booster of the land launched one, because
a) The plane itself provided a "boost", and
b) The altitude at which the plane was at also provided a "boost"
At no point in time that I can recall was the plan to accept a lower range.

So, this lower range for the air launched missile is rather perplexing.

I suspect it is because of some limitation within the MKI itself that it could not host a larger missile- with the larger range. Or it could be because they wanted more than one missile per MKI and for that they needed a mush smaller missile.

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Re: Indian Missiles and Munitions Discussion

Postby akimalik » 18 Nov 2012 09:25

related to the BrahMos, can anyone share the liquid fuel used in the missile?
I wanted to know whether the fuel used by the missile is similar (or same) as ATF class fuels?

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Re: Indian Missiles and Munitions Discussion

Postby Singha » 18 Nov 2012 09:29

it is aviation fuel of some unknown type - ie purified kerosene with some additives.

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Re: Indian Missiles and Munitions Discussion

Postby member_23651 » 18 Nov 2012 10:15

NRao wrote:The original plan, for an air based Brahmos, was to have a smaller booster (as compared to a land launched one) because:
1) The MKI could not carry the weight of the land launched one,
2) The air launched one did not need a booster of the land launched one, because
a) The plane itself provided a "boost", and
b) The altitude at which the plane was at also provided a "boost"
At no point in time that I can recall was the plan to accept a lower range.

So, this lower range for the air launched missile is rather perplexing.

I suspect it is because of some limitation within the MKI itself that it could not host a larger missile- with the larger range. Or it could be because they wanted more than one missile per MKI and for that they needed a mush smaller missile.

Lower range for air launched brahmos? As far as I remember it is same as the official range of land based Brahmos :P 8)

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Re: Indian Missiles and Munitions Discussion

Postby member_23370 » 18 Nov 2012 11:45

The range is same the missile is shorter.

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Re: Indian Missiles and Munitions Discussion

Postby Kersi D » 18 Nov 2012 14:19

Singha wrote:it is aviation fuel of some unknown type - ie purified kerosene with some additives.


Mr Singha. All aviation fuel, ATF, is purified kerosene.

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Re: Indian Missiles and Munitions Discussion

Postby akimalik » 18 Nov 2012 15:10

Kersi D wrote:All aviation fuel, ATF, is purified kerosene.


is it possible that the fuel used on the BrahMos is same/similar to the one used by the mother a/c?
in that case, is it feasible that the BrahMos is loaded on a wet pylon, but its fuel tank is empty.
the mother a/c then takes off with the empty BrahMos which fills up the missile in-flight using its own on-board fuel.
my point is that in such cases, AAR might help the mother a/c take-off with a lighter load and then tank-up the missile mid-flight prior to actual launch.
is this feasible considering that the a/c and missile use similar (or hopefully identical) fuels?

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Re: Indian Missiles and Munitions Discussion

Postby Kersi D » 18 Nov 2012 16:00

akimalik wrote:
Kersi D wrote:All aviation fuel, ATF, is purified kerosene.


is it possible that the fuel used on the BrahMos is same/similar to the one used by the mother a/c?
in that case, is it feasible that the BrahMos is loaded on a wet pylon, but its fuel tank is empty.
the mother a/c then takes off with the empty BrahMos which fills up the missile in-flight using its own on-board fuel.
my point is that in such cases, AAR might help the mother a/c take-off with a lighter load and then tank-up the missile mid-flight prior to actual launch.
is this feasible considering that the a/c and missile use similar (or hopefully identical) fuels?


This was done by USAF with their B 52s armed with Hound Dog air-to-surface (N) missiles.

The B 52 pilots would even start Hound Dog's engines and it shortened the TO run of the B 52. The Hound Dog's tanks were then topped with the fuel from the mother B 52.

But....

The AGM 28 Hound Dog was a jet propelled missile, jet similar to the J75 engines. Does Brahmos have any jet engines ?

K

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Re: Indian Missiles and Munitions Discussion

Postby vivek_ahuja » 18 Nov 2012 17:28

Kersi D wrote:Does Brahmos have any jet engines ?


The engine is different but the thermodynamics are still grounded in the same pot. The brahmos still depends on subsonic combustion of fuel despite the overall supersonic flight profile. The thing I am unaware of is whether the same grade of Kerosone is used or not.

More to the point, regardless of the fuel question, I feel the bigger question is whether this whole scheme is even needed. The SU-30 pylon being modified is from structural standpoint of having to bear 3000 kg mass of missile, whether at takeoff or otherwise. Even if the missile is empty, it still has the same wetted external surface and same geometry hence the same drag as before. Granted that the range of the aircraft can be extended by making it lighter initially, but can't that be done with Air-to-Air refuellers if required? So why to eat with hand around the head instead of the normal way to do so?

My two cents onlee...

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Re: Indian Missiles and Munitions Discussion

Postby vivek_ahuja » 18 Nov 2012 17:32

First Part of a five part series of papers I am writing:

The Agni-I Ballistic Missile: Vivek Ahuja

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Re: Indian Missiles and Munitions Discussion

Postby NRao » 18 Nov 2012 21:11

AnantS wrote:Lower range for air launched brahmos? As far as I remember it is same as the official range of land based Brahmos :P 8)


Ouch. You are right.

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Re: Indian Missiles and Munitions Discussion

Postby gnair » 19 Nov 2012 00:22

@Vivek_ahuja ....jmt only
I don't think the Agni 1 is 'Pak Specific' anymore, although it may have been, while on the drawing board. Don't you think this is emerging as a weapon of choice in the Tibet theater, if the PLA decided to use their M-9/M-11 and TU-16 air launched cruise miss. at standoff range, just in case they get the shivers sending in their manned J-10's and J-11's. The counter strategy would start with Prahar, BM-30 Smerch-ER, Prithvi's and Agni-1's to take the juice out of the conscripts. I don't see the liquid Prithvi in inventory for much too long, maybe the solid fuel ones, once the inventory reaches optimal levels.
Keep up the good work!

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Re: Indian Missiles and Munitions Discussion

Postby member_23370 » 19 Nov 2012 05:06

Agni-I has range >1000 km and ideal for Tibet. But it will hopefully be superseded by Shaurya missile. Why do you need it for pakis? Brahmos (500 km) along with Prahaar and Smerch will do. Though a lot of 155mm guns are required.

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Re: Indian Missiles and Munitions Discussion

Postby gnair » 19 Nov 2012 05:37

Yes indeed, add Shaurya's and CBU-105 to the offensive weapons ORBAT.

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Re: Indian Missiles and Munitions Discussion

Postby vivek_ahuja » 19 Nov 2012 07:15

gnair wrote:I don't think the Agni 1 is 'Pak Specific' anymore, although it may have been, while on the drawing board. Don't you think this is emerging as a weapon of choice in the Tibet theater, if the PLA decided to use their M-9/M-11 and TU-16 air launched cruise miss. at standoff range, just in case they get the shivers sending in their manned J-10's and J-11's. The counter strategy would start with Prahar, BM-30 Smerch-ER, Prithvi's and Agni-1's to take the juice out of the conscripts. I don't see the liquid Prithvi in inventory for much too long, maybe the solid fuel ones, once the inventory reaches optimal levels.


From a technical standpoint, you are absolutely correct. And the range/payload chart in there suggested the same idea to me as well when I was writing the article.

In a few years, when the numbers of missiles available increases in the inventory, then Agni-I will take different roles and one of them will be a conventional role in Tibet. Same argument for the Shaurya as well.

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Re: Indian Missiles and Munitions Discussion

Postby Singha » 19 Nov 2012 08:01

does anyone know the plans and deployment status of the Shourya. so far no open source news when its trials period will be over, no news of user trials, which agency IA or SFC will own it, production order and how it fits the matrix alongside A-1.

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Re: Indian Missiles and Munitions Discussion

Postby Gagan » 19 Nov 2012 09:11

These guys don't mention Shourya as deployed. They are outdated though.

Bulletin of Atomic Scientists: Indian Nuclear Forces 2012
pdf download link

Bulletin of Atomic Scientists: Pakistan Nuclear Forces 2012
pdf download link

Bulletin of Atomic Scientists: Chinese Nuclear Forces 2012
pdf download link

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Re: Indian Missiles and Munitions Discussion

Postby member_20317 » 19 Nov 2012 12:14

http://news.outlookindia.com/items.aspx?artid=352789

A dated article. Sorry about that, except that I wanted to bring forth this thing mentioned in the article:

Natarajan said defence scientist were also working on the profile to develop 1,000 KM range surface-to-surface supersonic cruise missile by enhancing capabilities of already deployed Indo-Russian Brahmos Missile.


All else mentioned in that article is already done or progressing well. So this supersonic cruise missile could only refer to Nirbhay. Perhaps in the endgame it goes supersonic (speculating off course). Anyways what for me is more important is a different speculation.That the Nirbhay is almost already tested in terms of its more crucial aspects, Guidance. Lately there was something about 500 km Brahmos. So the whole thing seems like an organic growth with our Sainsdaan working mainly to absorb the Guidance systems and having made progress to that extent.

That also carries implications for where the thanks is due.

Could that explain the khujli for Canisterized Testing.

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Re: Indian Missiles and Munitions Discussion

Postby SSridhar » 19 Nov 2012 15:54

Singha wrote:does anyone know the plans and deployment status of the Shourya. so far no open source news when its trials period will be over, no news of user trials, which agency IA or SFC will own it, production order and how it fits the matrix alongside A-1.

AFAIK, the missile is under production. A very successful user trial was conducted on Sep. 24, 2011 when the missile flew at Mach-7. I do not expect this missile to be under SFC control.

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Re: Indian Missiles and Munitions Discussion

Postby Austin » 19 Nov 2012 16:00

NRao wrote:2) The air launched one did not need a booster of the land launched one, because
a) The plane itself provided a "boost", and


The Air Launched Brahmos does need a booster but a smaller one compared to ground launched one since you need to boost the missile to supersonic speed before the ramjet takes over.

You can fly aircraft always at supersonic speed infact fighter aircraft rarely fly supersonic.

So eventually you get the advantage even in subsonic speed of 0.7M plus a smaller booster then is needed to make that into supersonic.


On another query you cant fill the fuel in the air for such missile , these are prefilled and sealed which can be used for 10 years

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Re: Indian Missiles and Munitions Discussion

Postby member_20317 » 19 Nov 2012 17:05

vivek_ahuja wrote:Exactly. The Brahmos would be easily reaching its theoretical ranges of around ~500 Km when launched from a carrier aircraft and thrown at targets on the Tibetan plateau.



While everything is somewhat speculative but YJ-12 and Perseus are two missiles that give reason to believe that even 500 km may be an understatement. Both these are featured on wiki.

Rangewise I have come round to the belief that Indian Establishment lies and intentionally lies unconvincingly.

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Re: Indian Missiles and Munitions Discussion

Postby saje » 19 Nov 2012 17:11

Is there a possibility of using a hypersonic vehicle as a booster to deliver a missile into it's target attack envelope, from where the missile can then engage it's intended target?

Image

The advantages would be:

1) We would not need to have multiple missiles of multiple ranges -- for eg, for air defence purposes we need not have QRSAM, MRSAM or LRSAM. We'll just need one missile type (eg SPYDER) of which one or more can be strapped onto the hypersonic booster depending on the flight profile needed.
2) Stationing of appropriate number of missile batteries in any threat location is redundant since using hypersonic booster, the missiles can be fired into the threat region from a faraway region as well.

Typical scenarios:

1) A red missile fired at Delhi from China can be engaged by a spyder missile battery based in Noida at multiple ranges -- over Arunachal, over U.P and finally over Delhi itself.
2) If the AA missile battery in any threat theater is out of missiles, missiles can be 'loaned to it' by an AA missile battery based in a non-threat theater.
3) An AWACS detecting a red missile threat (which is not yet detected by ground-based radars), can take control of any on-line missile battery anywhere in India and fire a missile towards the red missile.

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Re: Indian Missiles and Munitions Discussion

Postby Kanson » 19 Nov 2012 18:26

Brahmos-2 is expected to be a re-usable missile exhibiting features similar to CVS401 Perseus concept from MBDA.

saje wrote:Is there a possibility of using a hypersonic vehicle as a booster to deliver a missile into it's target attack envelope, from where the missile can then engage it's intended target?


You are talking about theater wide SAM system with hypersonic booster. Of course possible. Aster family do have such concept. But in case of SAM, response time is critical. And then there is economics and many other factors to be considered.

But before that, fighter Sqdns deployed with AWACS can take control of such threat.

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Re: Indian Missiles and Munitions Discussion

Postby Singha » 19 Nov 2012 18:27

hypersonic != cheap

they will be Nx more costly than a brahmos for sure given the exotic materials and project cost involved.

might be reserved for high value roles.

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Re: Indian Missiles and Munitions Discussion

Postby Kanson » 19 Nov 2012 18:39

ravi_g wrote:http://news.outlookindia.com/items.aspx?artid=352789

A dated article. Sorry about that, except that I wanted to bring forth this thing mentioned in the article:

Natarajan said defence scientist were also working on the profile to develop 1,000 KM range surface-to-surface supersonic cruise missile by enhancing capabilities of already deployed Indo-Russian Brahmos Missile.


All else mentioned in that article is already done or progressing well. So this supersonic cruise missile could only refer to Nirbhay. Perhaps in the endgame it goes supersonic (speculating off course). Anyways what for me is more important is a different speculation.That the Nirbhay is almost already tested in terms of its more crucial aspects, Guidance. Lately there was something about 500 km Brahmos. So the whole thing seems like an organic growth with our Sainsdaan working mainly to absorb the Guidance systems and having made progress to that extent.

That also carries implications for where the thanks is due.

Could that explain the khujli for Canisterized Testing.


Sirji, in today's world any motivated industrial country can make rudimentary Cruise missile provided it do have access to some moderate mini turbo engine. But what differentiates between an ordinary Cruise missile and world class state of the art one is the Guidance and additionally its sensor.

One can understand the importance of Guidance as we go through the failures of Cruise missiles.

So do ask what differentiates and what made Brahmos world class missile from Yakhont misile. The answer, of all other things, is Guidance.

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Re: Indian Missiles and Munitions Discussion

Postby sum » 20 Nov 2012 08:21

The Hindu has a article today mentioning that the K-15 is ready for induction and has already been placed into production after its last successful test off Vizag.
The K-4 will undergo pontoon trials later this year/early next year.

Anyone able to locate the article in online edition?

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Re: Indian Missiles and Munitions Discussion

Postby RajSingh » 20 Nov 2012 09:18


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Re: Indian Missiles and Munitions Discussion

Postby SSridhar » 20 Nov 2012 10:42

I am posting the above article in full, courtesy The Hindu.

India will shortly induct K-15 missiles armed with nuclear warheads into INS Arihant, the indigenously built nuclear-powered submarine.

This follows several successful launches of K-15 missiles from a pontoon off the Visakhapatnam coast. Informed Defence Research and Development Organisation (DRDO) sources told The Hindu that all the trials of K-15 which has a strike range of 700 km have been completed and its production had already begun.

Sources said India was the fifth country to have this kind of technology, where a missile carrying a nuclear warhead could be launched from under the water. The other four countries are the United States, Russia, France and China. “This technology is complex because the missile is launched from under the water and it is launched from a manned platform [submarine]. So, safety of the personnel on board is of paramount importance. Safety and reliability of the systems should be very high,” the sources added.

Arihant will carry 12 K-15 missiles. Besides Arihant, which has been built at the Visakhapatnam Naval Dock Yard, India is building two more nuclear-powered submarines for commissioning into the Navy and their hulls are being fabricated at Vadodara.

After its launch from under water, the 10-metre tall K-15 will rise to an altitude of 20 km and cover a distance of 700 km. A gas generator will push K-15 from out of water. Arihant’s reactor will be commissioned by the end of this year, informed sources said.

Arihant is powered by an 80 MWt (thermal) nuclear power reactor which uses enriched uranium as fuel and light water as both coolant and moderator. The enriched uranium has been fabricated at Rare Materials Plant at Ratnahalli, near Mysore.

The nuclear power reactor which will propel Arihant is similar to the Light Water Reactor commissioned at Kalpakkam. The Kalpakkam reactor also has capacity of 80 MWt and is being used to train the Naval personnel who will be manning Arihant and the other nuclear-powered submarines under construction.

The DRDO is developing another submarine-launched missile, K-4 which will have a range of 3,000 km. The first flight trial of K-4 will be conducted soon from a submerged pontoon off Visakhapatnam. {AoA}

Once the n-powered submarines carrying the K-series get inducted, the triad of India’s nuclear deterrence capability will be completed. While the Agni series forms the mainstay of the land leg, fighter aircraft Sukhoi-30 and Mirage-2000 will deliver warheads for the air version.


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Re: Indian Missiles and Munitions Discussion

Postby merlin » 20 Nov 2012 12:42

I hope that that K4 has a range of 3000 kms. for a 3 ton payload :-)

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Re: Indian Missiles and Munitions Discussion

Postby dinesha » 20 Nov 2012 12:58

This follows several successful launches of K-15 missiles from a pontoon off the Visakhapatnam coast. Informed Defence Research and Development Organisation (DRDO) sources told The Hindu that all the trials of K-15 which has a strike range of 700 km have been completed and its production had already begun.

Few trial launches needs to be carried out from actual submerged platform..

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Re: Indian Missiles and Munitions Discussion

Postby Aditya_V » 20 Nov 2012 13:32

What does 80MWT transalte to in MWE? 16?

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Re: Indian Missiles and Munitions Discussion

Postby dinesha » 20 Nov 2012 14:05

^^33 MWe Approx

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Re: Indian Missiles and Munitions Discussion

Postby nachiket » 20 Nov 2012 23:42

^^Wouldn't that depend on the efficiency of the reactor?

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Re: Indian Missiles and Munitions Discussion

Postby Kersi D » 21 Nov 2012 00:43

nachiket wrote:^^Wouldn't that depend on the efficiency of the reactor?


It would depend more on the efficiency of the turbine
K

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Re: Indian Missiles and Munitions Discussion

Postby SaiK » 21 Nov 2012 00:50

did they say, everything is ready to go on the reactor ?

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Re: Indian Missiles and Munitions Discussion

Postby pentaiah » 21 Nov 2012 01:22

Kersi D wrote:
nachiket wrote:^^Wouldn't that depend on the efficiency of the reactor?


It would depend more on the efficiency of the turbine
K


true if its steam turbine direct propulsion.

The main difference between conventional submarines and nuclear submarines is the power generation system. Nuclear submarines employ nuclear reactors for this task. They either generate electricity that powers electric motors connected to the propeller shaft or rely on the reactor heat to produce steam that drives steam turbines (cf. nuclear marine propulsion). Reactors used in submarines typically use highly enriched fuel (often greater than 20%) to enable them to deliver a large amount of power from a smaller reactor and operate longer between refuelings – which are difficult due to the reactor's position within the submarine's pressure hull.



Image


Image

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Re: Indian Missiles and Munitions Discussion

Postby kit » 21 Nov 2012 13:02

If a pumpjet propulsion is used would a nuclear reactor have more efficiency ?

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Re: Indian Missiles and Munitions Discussion

Postby Kersi D » 21 Nov 2012 13:05

pentaiah wrote:
Kersi D wrote:It would depend more on the efficiency of the turbine
K


true if its steam turbine direct propulsion.

The main difference..... ............. Nuclear submarines employ nuclear reactors for this task. They either generate electricity that powers electric motors connected to the propeller shaft or rely on the reactor heat to produce steam that drives steam turbines (cf. nuclear marine propulsion). Reactors used in submarines typically use highly enriched fuel (often greater than 20%) to enable them to deliver a large amount of power from a smaller reactor and operate longer between refuelings – which are difficult due to the reactor's position within the submarine's pressure hull.


There is no way a nuclear reactor can directly "generate electricity that powers electric motors connected to the propeller shaft". Essentially a nuclear reactor generates heat which in turn generates steam. This steam can be used to drive a propellor / shaft in a ship or a turbo generator to generate power either on land or at sea.

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Re: Indian Missiles and Munitions Discussion

Postby Singha » 21 Nov 2012 13:23

a pumpjet propulsor might need more power. someone has got to force this water into the funnel


It funnels water through a lampshade causing an increase in pressure at the locations where the blades slices through the fluid media. This increase in pressure delays the onset of cavitation. Cavitation happens when vaccuum "bubbles" form at the trailing edges of the blades when they travel through the liquid faster than the water can rush back in to fill the void they leave as they pass. As pressures increase, the propeller at which the onset of cavitation occurs also increases. This is why subs are "silent" up to a higher speeds as they dive deeper.

The lamp shade also shields the sound made by the propeller in most of the lateral directions. This makes the sub quieter laterally but may increase their sound signature longtidually -- especially dead astern.

The Ohios are very quiet with or without a pumpjet propulsor. They are quiet enough that the soviets are said to have never tracked one after it dives in deep water. One of the features of the submarine is that at slow speeds (low reactor output) the coolants are circulated through the core through natural convection without any pumps being used. The Ohios spent most their time at very slow speeds while on patrol. At 3~5 knots, it is doubtful if a pumpjet makes a difference.


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