INS Arihant (ATV) News and Discussion -2

sbangera · Post by **sbangera** » 01 Jun 2010 20:16

Finally get to see the monstor. Thanks Austin.

karan_mc · Post by **karan_mc** » 01 Jun 2010 20:18

Daaniya hai maine toh bagwaan ko dek leya aaj , looks good

pushkar.bhat · Post by **pushkar.bhat** » 01 Jun 2010 20:56

Finally the Arihant has been seen.

bahdada · Post by **bahdada** » 01 Jun 2010 21:02

She's a beaut. Hope I'll be lucky enough to stop her off RK Beach in couple of years.

Singha · Post by **Singha** » 01 Jun 2010 21:06

reading the tea leaves two more sister ships would be deep into construction. we can likely expect the #2 sister to be completed in 2011 and last in 2013 perhaps.

after that 3 + 3 SSBN & SSN approved by goi in 2005. so expect a SSBN and SSN construction line to operate in parallel. the SSBN will likely be 12000t+ and have a "proper" 12 tubes. room enough to fit sub caliber nirbhay tubes tipped with tactical nukes should we choose to pursue
colonial wars on terrorist compounds.

whispers in other forums speak of the A3SL having a massive throw weight @ 5500km to account for heavier boosted fission warhead vs 700kg throw weight of chini "icbm" @ 7000km.

other whispers speak of the reactor being critical and developing much more power than we initially thought. top speed expected to be ~32 knots
and the sleek 688 style hull shape backs it up

we are going to need to test new designs and fixes to thermo nuclear devices around 2015-2020 to "properly" target P3 cities far beyond oceans with 300kg devices. hopefully the financial situation will be much in our favour by then.

Gagan · Post by **Gagan** » 01 Jun 2010 21:08

That's a smart looking sub!

The anechoic tiles are really shining, and they give the surface that uneven look.

But the photo quality sucks big time. It is not helped by the sodium lamps inside the covered dockyard, and strong sunlight on the outside. Perhaps the phtographer's equipment could have been better. They should get Kedar Karmakar to do a photo walkaround the sub.

Singha · Post by **Singha** » 01 Jun 2010 21:11

> They should get Kedar Karmakar to do a photo walkaround the sub.

he is so thorough might as well fedex the design drawings to all who ask

sum · Post by **sum** » 01 Jun 2010 21:14

Finally the babe has revealed herself!!!!!!! A satisfied jingo can go to bed now....

Thanks to the kind soul who put up the pic since tired of seeing Mrs. MMS and the coconut in her hand till now ( as aptly predicted by Gagan-ji before the initial commissioning took place)

Rahul M · Post by **Rahul M** » 01 Jun 2010 21:15

Gagan wrote: Perhaps the phtographer's equipment could have been better. They should get Kedar Karmakar to do a photo walkaround the sub.

jingos are never satisfied !

interesting to note that the control surfaces are on the sail similar to western subs rather than on the hull like russki ones.

question time, is there a hump or not ? I can't make out due to the glare, perhaps some PS expert can change tones and tell us ?

Tanaji · Post by **Tanaji** » 01 Jun 2010 21:17

Stupid question: Why doesnt it have a conventional tear drop shape? Obviously the designers must have done it on purpose, just trying to understand why?

Misraji · Post by **Misraji** » 01 Jun 2010 21:24

^^^^
Whoa, whoa, whoa !!! ..
Is that an open missile tube behind the sail? ....Very cool ...

Sail-planes as opposed to bow planes for better control.
We are too far away from the arctic, I guess.
Anyway, the sail planes differentiates this babe from any Russian sub, I guess.

Isn't that kind of flooding arrangement (the long slit as opposed to free flooding holes)
indicative of single hulled submarine? I always thought the ATV was a double hulled.

~Ashish.

Rahul M · Post by **Rahul M** » 01 Jun 2010 21:27

err, it is a teardrop shape. teardrop just means a smooth structure designed for superior underwater performance unlike earlier subs which were shaped more like surface ships.

Gagan · Post by **Gagan** » 01 Jun 2010 21:29

I played around with an image editing software to see if I could see anything more in that picture.

Rahul M · Post by **Rahul M** » 01 Jun 2010 21:32

thanks gaganji, just what I was talking about. so there appears to be a hump.
/greedy mode on
can we please have an estimate of the dimensions ?

Gagan · Post by **Gagan** » 01 Jun 2010 21:36

And you can just see the door used to load torpedoes into the sub just below the white sonar. It is halfway on bothsides of the white line.
That is too big to be a torpedo tube door, which I suspect would be just below water level.

Singha · Post by **Singha** » 01 Jun 2010 21:40

I feel its higher in the water than would be normal. the red part would likely be submerged when fully loaded and trimmed.

hard to say with one pic but could have gone for as semi "astute" class type design where its not a perfect cylinder but taller than its wide
http://www.royalnavy.mod.uk/upload/img_ ... w4_RGB.jpg

this would keep size small but accomodate 10m tubes.

Singha · Post by **Singha** » 01 Jun 2010 21:47

note on bow planes vs sail planes. the 688 had on sail, 688I on bow. almost all pix of US sub surfaced through artic ice are 688I (no sail fin) but I saw one earlier of a 688 with its sail fins folded down or behind( cant remember now).

"Once the boat is trimmed to more or less neutral buoyancy, the depth of the boat is controlled with the hydroplanes. To use the hydroplanes the boat requires speed to create a force on the tilted planes. At slow speeds, the fore hydroplanes are exclusively used to keep the boat at the required depth. The fore planes can be located on the hull near the bow or on the sail of the boat. Because bow mounted hydroplanes are located further from the center of gravity, the depth control is more accurate with these types. Arguments for locating the fore planes on the finn of the boat are (a) improved performance of the spherical sonar array in the bow because the fore hydroplanes generate noise and (b) bow mounted hydroplanes can be damaged during docking of the submarine. Penalties for placing the fore planes on the fin are (a) the operating gear takes up space in the fin where room badly is needed for the masts, (b) the ice breaking performance is decreased, (c) at periscope depth the planes are close to the surface so their performance is adversely affected by the surface turbulence and finally (d) the hydroplanes are closer to the center of gravity and are thus less effective. Note that while improving the Los Angeles class submarine (688I) the US Navy relocated the fore planes from the sail to the bow. At sufficiently high submerged speed (more than 12 knots), the fore planes are no longer needed to control the depth of the submarine. At these speeds, they are rotated in a neutral or slightly dive position. Because the fore planes generate noise, many submarines are capable of retracting the forward bow planes at high speeds. All this considering, we may conclude that (retractable) bow planes are more favorable. It may be added that the author is not aware of boats having both dive planes on the bow and on the sail. "

Gagan · Post by **Gagan** » 01 Jun 2010 21:48

Not much you can see on a picture of the outside of a submarine:

AND as if on cue, google earth has updated the picture of Vishakapatnam dockyard. INS Virabhu and the new sub pen now completed are visible.
There are two foxtrots visible, two kilos, and one kilo in a dry dock.
One fat and guppy INS Jalashwa is visible.
No arihant is visible

Gagan · Post by **Gagan** » 01 Jun 2010 21:52

Singha wrote:I feel its higher in the water than would be normal. the red part would likely be submerged when fully loaded and trimmed.

I thought about this when N^3 came up with the theory that a subs loadout could be arrived at by looking at its displacement as it exits the dock.

But here lies the magic of a submersible like a sub. The crew can alter its depth by keeping its tanks somewhat flooded so that the water line corresponds to the water level outside.

Misraji · Post by **Misraji** » 01 Jun 2010 22:00

Gagan wrote:And you can just see the door used to load torpedoes into the sub just below the white sonar. It is halfway on bothsides of the white line.
That is too big to be a torpedo tube door, which I suspect would be just below water level.

Torpedo-loading
Mk-48 being loaded.

Torpedo loading arrangement so near the waterline does not exactly make sense.
Those are probably the torpedo tubes below the sonar.

~Ashish

Singha · Post by **Singha** » 01 Jun 2010 22:05

uk/usa subs have this top hatch with inclined tube which feeds into the torpedo room. the kilo class has a front loading port about where
gagan is pointing
http://www.naval-technology.com/project ... o8779.html

the torpedo tubes would be in a row just below it.

this cutaway claims kilo has 6 tubes and the two on top might be reused as loading tubes too.
http://www.armybase.us/wp-content/uploa ... rine-2.JPG

Gagan · Post by **Gagan** » 01 Jun 2010 22:06

Ashish,
Those are MK-48 torpedoes loading on a US Navy sub. Now these subs have angled side firing torpedo tubes, and the torpedo room is midship.
The Arihand borrows from the Kilo class design in the front end. The sonar housing that is visible is nearly the same as on the kilo.
This picture is a better comparision:

These are Klub missiles being loaded onto the sub through the torpedo tube. The Arihant will probably carry the Klub missile too.

Misraji · Post by **Misraji** » 01 Jun 2010 22:09

[nagging-mode]
The sail design is a bit disappointing though.
Was hoping that it would be more beautiful, somewhat along
the lines of Akula class or Victor-III.
[/nagging-mode]

~Ashish

Misraji · Post by **Misraji** » 01 Jun 2010 22:10

Gagan wrote:Ashish,
Those are MK-48 torpedoes loading on a US Navy sub. Now these subs have angled side firing torpedo tubes, and the torpedo room is midship.
The Arihand borrows from the Kilo class design in the front end. The sonar housing that is visible is nearly the same as on the kilo.
This picture is a better comparision:
..

Oh. I did not know that.
Very cool. Thanks.

~Ashish.

Singha · Post by **Singha** » 01 Jun 2010 22:12

in kilo is the top two tubes tied to loader but otherwise fully functional to fire torpedoes too?

in that case arihant might also have same arrangement of 2 + 4 ?

wrt sail design, even Rus has moved away from akula style for Borei ssbn while retaining it for sverodbinsk. we need an explanation why
it was not used for borei.

Kartik · Post by **Kartik** » 01 Jun 2010 22:12

Great karma to Shiv Aroor for putting this pic up ! This should silence one particular know-it-all Russophile on this very forum who was going around gassing about the Arihant being a copied design of an Akula submarine itself..he now does it on Suman Sharma's blog, apart from openly flirting with her. the Arihant looks nothing like an Akula with those hydroplanes..this settles that issue once and for all. Now if we can just get a good clean image of the Arihant..can't make out if there is a boom or not.

Singha · Post by **Singha** » 01 Jun 2010 22:15

this pic clarifies the matter. there is a single small reload port between the top 2 tubes !

http://flot.sevastopol.info/photos/phot ... 871_03.jpg

looking closely at arihant I can clearly make out the big circular top torpedo tubes with the smaller loading port in between.

Singha · Post by **Singha** » 01 Jun 2010 22:16

Gagan you have mislabelled it I think. the "torpedo loading door" is the right torp tube. the smaller circle next to it is the loading door and beyond that part of the left tube is also visible.

Gagan · Post by **Gagan** » 01 Jun 2010 22:16

Have a look at the pictures in this link:
http://www.defencetalk.com/pictures/sho ... hoto/11313

Gagan · Post by **Gagan** » 01 Jun 2010 22:19

The Akula class subs have a slightly different torpedo loading doors.

No auto loader required onlee.

Singha · Post by **Singha** » 01 Jun 2010 22:22

ok..so looks like the center hole opens and acts as some kinda machinery support I guess. the PLAN folks have that hatch open too.

Misraji · Post by **Misraji** » 01 Jun 2010 22:26

Singha wrote: wrt sail design, even Rus has moved away from akula style for Borei ssbn while retaining it for sverodbinsk. we need an explanation why it was not used for borei.

Could be ease of construction. Akula-style design offers higher performance that is needed for a SSN
but arguably not for a SSBN sailing in protected waters.

~Ashish.

Gagan · Post by **Gagan** » 01 Jun 2010 22:32

Singha wrote:Gagan you have mislabelled it I think. the "torpedo loading door" is the right torp tube. the smaller circle next to it is the loading door and beyond that part of the left tube is also visible.

I think you are right.
I can see another door on the opposite side. Looks like the torpedo tube arrangement is just like the kilo.

Gagan · Post by **Gagan** » 01 Jun 2010 22:33

Well Hats off to Shiv Aroor for publishing the first ever pictures of the Arihant on his blog

Singha · Post by **Singha** » 01 Jun 2010 22:33

the small middle door supplies some electrical power or support to the loading ramps on the two tubes I think. so you labelling is correct and
actual loading takes place via the two upper tubes as seen in PLAN pix.

sail shape : could be. but even the platinum bullet seawolf and the "cheap" virginia didnt use the akula style...though it looks sleek and a no-brainer.

Samay · Post by **Samay** » 01 Jun 2010 22:38

Rahul M wrote: can we please have an estimate of the dimensions ?

Length would be similar to an Akula class

ramana · Post by **ramana** » 01 Jun 2010 22:41

That white line could be the sea water line.

svinayak · Post by **svinayak** » 01 Jun 2010 22:42

Kartik wrote:Great karma to Shiv Aroor for putting this pic up ! This should silence one particular know-it-all Russophile on this very forum who was going around gassing about the Arihant being a copied design of an Akula submarine itself..

From outside it looks like a Los Angeles class SS to me.

Suraj · Post by **Suraj** » 01 Jun 2010 22:58

What a great way to start the day! Amazing first picture of the Arihant.

Is that really just 6000 tons ? It 'looks' bigger. Very un-Russian features.

Kartik · Post by **Kartik** » 02 Jun 2010 00:05

Acharya wrote:
Kartik wrote:Great karma to Shiv Aroor for putting this pic up ! This should silence one particular know-it-all Russophile on this very forum who was going around gassing about the Arihant being a copied design of an Akula submarine itself..
From outside it looks like a Los Angeles class SS to me.

More like an Ohio Class SSBN..the Los Angeles class has a very circular shaped hull. the Arihant OTOH has a marked flat top and then shapes away to what might be a circular or ogival cross-section.

Ohio Class SSGN