[ads11]

Originally Posted by V.Narayan

[b]
The French have offered to work with Maz Docks on 3 more Scorpene submarines to bridge the gap and keep the production line ticking till the P-75I project comes on stream. To me this sounds like a sensible path to pursue given how much effort, training and investment goes into building the supply chain locally. Six submarines is not a large enough number to build an industrial eco-system around of ancillary suppliers. Let's hope sound sense will prevail. God only knows we need those submarines.

I thoroughly agree!! In all reality the best case for the IN is to get additional Scorpene hulls through the procurement door. In that sense the damn bureaucrats with the purse strings get their most beloved result - time to punt the P75I decision to further down the line, so they can strew over "all the factors in due time". Argh!

6 hulls is nowhere near enough for our needs and considering we are just about coming to grips with local production, the very best thing we can do is keep that momentum. That way, realistically what will happen is that the Block 1 IN Scorpenes shall we say, can undergo the logical upgrades later down the line, there being at that point a mature and integrated supply and manufacturing chain in existence with a solid decade of experience behind it. At that point we'll be best placed to take the P75I on (personally I think we should put our eggs in the Naval Group basket - we'll be experienced Scorpene operators by that point - might as well double down on the same family than needing yet Another disparate supply chain for parts and maintenance). Also as the supersized Barracuda shows, Naval Group (formerly DCNS) have experience in scaling up an existing design of theirs to meet new project requirements. I realise I often reiterate my points..apologies!

Think about it, we'll have 2 main zones to cover. 2 of those boats will be in for refit and deep repair, at least 1 will be on training, if not 2, which only leaves 2 for on station time. At most I think realistically surge 3 at a time and that'll limit which sector we focus on. V Narayan is absolutely correct, we probably need at least 10 considering the fact that by the time the 6th Scorpene rolls off the line, it'll come time for some of the older boats in the fleet to call it a day, if they haven't been scuppered by misfortune at that point.

[ads11]

https://www.forbes.com/sites/hisutto.../#554bab397212

HI Sutton for those in the know is quite the authority on the subsea domain, so if his eagle eyes have spotted this I'd look closely. We might be getting a glimpse of the latest IN SSBN.



You can see it in the bottom left in the foreground. It's a hydrodynamic model. So think of it like a wind tunnel scale model but in a test tank. The key differences seem to involve the humped back, where the ballistic missiles will be stored. Apparently it looks larger, to cope with carrying far more than the INS Arihant can for example (12 vs 4 respectively). So I imagine scale model testing is probably underway for how a larger hunchback so to speak would affect the boats performance in the water. At the very least its a small but tangible sign that Some work is indeed taking place in such a key strategic programme.

[V.Narayan]

Originally Posted by ads11

HI Sutton for those in the know is quite the authority on the subsea domain, so if his eagle eyes have spotted this I'd look closely. We might be getting a glimpse of the latest IN SSBN.

The key differences seem to involve the humped back, where the ballistic missiles will be stored. Apparently it looks larger, to cope with carrying far more than the INS Arihant can for example (12 vs 4 respectively).

+1 to that. That is a huge turtle back. I am also intrigued by the very broad beam of the tail fin!

[ads11]

Originally Posted by V.Narayan

+1 to that. That is a huge turtle back. I am also intrigued by the very broad beam of the tail fin!

Good spot! That fin is practically hydrofoil sized! No way it's that big on the final iteration. Actually that makes me wonder just how much is true to scale.. Before we end up going down the rabbit hole discussing based on 1 obscure image, they could just be so cartoonishly out of proportion because they might be testing end members to get a calibration range. Any way, interesting little snippet.

[Maveryq]

INS Khanderi to be commissioned on the 28th of September. 2nd of the 6 Scorpenes.


INS Karanj and INS Vela have already been launched and should be commissioned over the next year or so.


INS Khanderi launching pictures from Twitter.

[V.Narayan]

^^^^^^
Thank you Maverq for sharing this good news :-)

The second Scorpene class SSK joins the fleet on 28/9 after completing about a year of sea trials and final fitting out. Khanderi is named after Maharaj Shivaji’s sea fort on India’s Western Coast. The new submarine will carry the crest and battle honours of INS Khanderi the Foxtrot class submarine that served the Indian Navy from 1968 to 1989.

INS Khanderi carries an armament of long range homing torpedoes that can be fired against ship or sub-surface targets, SM39 Exocet submarine underwater launched anti-ship sea skimming missile and sea mines. While exact details of the torpedoes are never shared most modern 533mm torpedoes have an effective range between 20 to 50 kms. Similarly the Exocet anti-ship missile has a range of well above 70 kms. The missile is housed inside a watertight launched capsule which is fired by the submarine's torpedo-launch tubes. On leaving the water, the capsule is ejected and the missile's motor is ignited. It then behaves like an normal sea skimmer. The missile will usually be fired at depth, which makes it particularly suitable for discreet submarine operations and gives a single submarine to hold and sanitize a large sea area of over 4000 sq kms.

Technical details:

Surface displacement: 1615 tonnes; Submerged displacement: 1775 tonnes

Length: 221 feet; Beam: 20 feet

Powerplant: Diesel-Electric comprising of 4 MTU diesels and a bank of 360 battery cells

Top speed: 20+ knots

Range: 12,000 kms+ cruising at 8 knots (~14 kmph); Loiter endurance on batteries claimed at 1020 kms. Probably significantly greater. The crew of 35 are equipped for a sailing endurance of 50 days at a time.

Diving depth: 350 metres. Almost certainly a lot greater in practise.

Weapons: 18 533mm heavy torpedoes or Exocet missiles or 30 sea mines or any combination of the three.

Being a modern submarine she carries a full suite of versatile active and passive sonars for detection, ranging, tracking and attack as well as anti-torpedo decoys and an integrated command and control system. Similarly all vibration creating machinery - diesels, electric motors, lifts, torpedo hoists etc even the mixie in the kitchen are mounted on rafts that absorb the vibrations thus minimizing the acoustic signature of the boat. The Scorpene's I would guess have sound detectors placed all around to measure and monitor their own acoustic signature. Quite possibly, in line with earlier French diesel-electrics, it has a small super silent creep motor to enable her to glide at a slow speed of 2 to 5 knots with minimum fuss.

In the last 5 years the Indian Submarine Arm has finally started receiving a shot in the arm (pun intended) with new boats joining in to enable the older Kilo’s to be eventually decommissioned.


INS Khanderi at her sea trials


SM39 Exocet missile encased inside its torpedo carrier that takes it up to the surface from the depths.


Exocet breaking away from the surface of the sea, ejecting its cannister and firing its motors.

https://www.youtube.com/watch?reload=9&v=O55T0nrwmpo

[Maveryq]

Originally Posted by V.Narayan

^^^^^^
Thank you Maverq for sharing this good news :-)

Khanderi is named after Maharaj Shivaji’s sea fort on India’s Western Coast.

Thank you, and beg to differ Sir, regarding the name.


The Fort itself is might be named after the Sawfish - called Khanderi in marathi.


The boats carry shark /stingray related names.


So,


Kalvari - Tiger Shark
Khanderi - Wide Snouted Saw Fish


Am not aware of the meanings of Vela, Vagir, Vaghsheer and Karanj.


Also, some pictures of the boat from twitter. It seems to have a rubber coating?

[ads11]

Originally Posted by Maveryq

Also, some pictures of the boat from twitter. It seems to have a rubber coating?

Guess it must be the anechoic tiles that are standard on subs. I like how your first image captures the old carrier in the backdrop. Some nice lines on it.

News from Livefist from my Twitter feed this morning - Apparently SAAB have pulled out of the tender and South Korea have made an entry instead. Wonder what reason SAAB will give, because this follow on submarine tender is a pretty big deal (as ever the promise of immense moolah vs the immense headache of having to deal with India with respect to procurement is always the issue for vendors)

https://twitter.com/livefist/status/...defence.com%2F

[Maveryq]

Some pics from the commissioning ceremony today of INS Khanderi and some general pics of the boat on its sortie itself. The sortie pictures look really great. Nice move by the Navy to showcase its gear this way.


Picture Source: Twitter Handles

[Jeroen]

What are those bits sticking out of the hull forward of the tower/sail. With those red bar protectors around it. (Third image from above). Some sort of sensors?

Thanks Jeroen

[V.Narayan]

[quote=Jeroen;4669599]What are those bits sticking out of the hull forward of the tower/sail. With those red bar protectors around it. (Third image from above). Some sort of sensors?/QUOTE] Such pieces can be anyone of the following - passive sonars, passive sonar ranging equipment, underwater telephone (only for very short distance with sub very close to surface). I am no expert. Just writing from general knowledge.

[Sutripta]

Originally Posted by Jeroen

What are those bits sticking out of the hull forward of the tower/sail. With those red bar protectors around it. (Third image from above). Some sort of sensors?

Unless very slow these protrusions are likely to be noise generating.
What is the max speed underwater for these submarines?

Regards
Sutripta

[ads11]

Originally Posted by Sutripta

Unless very slow these protrusions are likely to be noise generating.
What is the max speed underwater for these submarines?

Regards
Sutripta

Max speed underwater and endurance are along with the acoustic signature bound to be amongst the most closely guarded secrets for a sub. I imagine all the numbers you Do end up finding in the public domain are probably massively fudged so as to not reveal what hand you're playing specs wise. All that being said the whole point of diesel electrics and especially AIP subs moving forward is their ability at creep speeds. As the name implies they'll practically be coasting so I suppose that's where whatever sensors they are come in handy. I don't imagine anything but the nuclear boats are putting on a turn of speed and hustling to a location. I always thought the whole point of conventional subs was to skulk around littorals or basically near the target harbours etc and shadowing other vessels.

And that's your non answer answer for the day! I'm probably about to get a recruitment flyer from LockMart as we speak..

Edit: also I just realised even for a newly commissioned vessel there might still be need for testing kit. Those could be bolt on bolt off sensors in that case. I can't really tell much more based on the photos and my limited knowledge

[Sutripta]

Originally Posted by ads11

And that's your non answer answer for the day!

(Non)thanks for the nonanswer!

You might be right that it is temporary. The red painted guards certainly are.

Regards
Sutripta

[V.Narayan]

Originally Posted by Sutripta

You might be right that it is temporary. The red painted guards certainly are.

Those are, in my mind at least, without doubt a part of the passive sensors package. Several submarines have them - British, French, Swedish for example. I am quite sure they are not temporary. The red guard is in place as the boat is berthed on the surface for a ceremony where land lubbers will be on the deck and you don't want them accidentally hitting it or falling over and damaging the radome. Radomes are typically made of a special plastic.