INS Vikrant: News and Discussion

Indranil · Post by **Indranil** » 16 May 2016 22:49

NRao wrote:AoA.
Plan for nuclear-driven carrier with US help

Sujan Dutta. Don't analyze based on his reports.

The aircraft carriers legs are not determined by propulsion alone. India might go for a nuclear-propulsion based aircraft carrier, but please wait for official sources. Navy is very forthcoming in its decisions.

ShauryaT · Post by **ShauryaT** » 16 May 2016 23:31

20MWe for two catapults from a 2*90 MWt provides you only about 10-12MWe for the rest of the ship, weighing 65K tons! Look at all the numbers more carefully. I believe one of the issues is the poor conversion from MWt to MWe based on Russian designs.

sudeepj · Post by **sudeepj** » 17 May 2016 02:23

Someone correct me if I am wrong, but the Cats get their energy from 'energy banks'. If you have a lower amount of power directed from your reactor, itll just take longer to charge up the energy bank, but itll still be fully charged. What you get is a lower launch rate, not an inoperational Cat.

Viv S · Post by **Viv S** » 17 May 2016 02:45

ShauryaT wrote:20MWe for two catapults from a 2*90 MWt provides you only about 10-12MWe for the rest of the ship, weighing 65K tons! Look at all the numbers more carefully.

How did you calculate that? Also how do you know they wouldn't supplement them power plant with a pair of LM 2500s?

The ship will require about 75 MW of shaft power (read: QE class - 70kt). Another 25 MW to run deck operations at peak frequency. That should still leave plenty of juice for rest of the ship. Especially if they can use the US assistance to shift to an all-electric design (like the Ford & QE classes).

I believe one of the issues is the poor conversion from MWt to MWe based on Russian designs.

Source? How do you know its based on a Russian design?

ShauryaT · Post by **ShauryaT** » 17 May 2016 03:23

Viv S wrote:
ShauryaT wrote:20MWe for two catapults from a 2*90 MWt provides you only about 10-12MWe for the rest of the ship, weighing 65K tons! Look at all the numbers more carefully.
How did you calculate that? Also how do you know they wouldn't supplement them power plant with a pair of LM 2500s?

The ship will require about 75 MW of shaft power (read: QE class - 70kt). Another 25 MW to run deck operations at peak frequency. That should still leave plenty of juice for rest of the ship. Especially if they can use the US assistance to shift to an all-electric design (like the Ford & QE classes).

I believe one of the issues is the poor conversion from MWt to MWe based on Russian designs.
Source? How do you know its based on a Russian design?

Lookup the conversion ratio from MWt to MWe for Russian designs. Compare top speed for given tonnage for Arihant. 90 MWt is the proposal from BARC to power the SSN. The Arihant reactor is a Russian design (we are done with the debate on that, please do not restart it, you can believe what you want). Also, that 75MW is like 75MW e (50,000 HP *2 gas turbines) to the shafts? that is huge (assuming that is the electrical conversion from thermal). The Akula 190MWt reactor provides only 29MWe. Also, did they not explore fitting the EMALS to the QE carriers and determined that the power requirements were at the edges and hence not viable. Anyways, as Indranilroy suggested the "report" seems speculative and does not pass my smell test.

NRao · Post by **NRao** » 17 May 2016 03:28

Viv S wrote: Especially if they can use the US assistance

Looks like certification + ops on Vikrant and design, construction, certification and ops on the Vishal. Vishal could come in earlier than expectations. I also would not be surprised if the Vishal gained some weight.

BTW, only 2 cats?

Viv S · Post by **Viv S** » 17 May 2016 04:35

ShauryaT wrote:Lookup the conversion ratio from MWt to MWe for Russian designs.

The Russians don't have any electric drives on warships, let alone on submarines.

Compare top speed for given tonnage for Arihant. 90 MWt is the proposal from BARC to power the SSN.

Its top speed has never been revealed. Top speed is primarily a function of its hydrodynamic design. And the design drivers there are acoustic.

The Arihant reactor is a Russian design (we are done with the debate on that, please do not restart it, you can believe what you want).

The debate may have ended but it ended on an entirely different consensus from your claim.

_________________________________________________________________________________

Asked whether the Russians helped in designing and building the PWR, Kakodkar, Banerjee and Basu were emphatic that BARC developed it on its own. Banerjee said: “The Russians were consultants. The consultancy was done for the whole submarine, not for the power part alone.” Basu asserted, “Everything is totally indigenous [in this PWR]…. We developed it. It is our own reactor. We did not take it from anybody else.”

M.R. Srinivasan, former AEC Chairman, was also emphatic that the DAE developed the reactor on its own. While building the reactor “was always a part of the DAE’s activity”, the Navy’s role was to design and build the submarine, he said. So it was a joint DAE-Navy project. Srinivasan said, “The naval personnel had some assistance from Russia in designing the submarine, but the reactor is a totally Indian effort. The reactor, its components including the pressure vessels, and its fuel were made in India by Indian industry.” - Link

Also, that 75MW is like 75MW e (50,000 HP *2 gas turbines) to the shafts? that is huge (assuming that is the electrical conversion from thermal). The Akula 190MWt reactor provides only 29MWe. Also, did they not explore fitting the EMALS to the QE carriers and determined that the power requirements were at the edges and hence not viable.

The QE delivers 80 MWe to the propulsion. The Russians' limitations in terms of transmission (or miniaturization) don't necessarily apply to India.

EMALS was considered in lieu of the riskier domestic Converteam EMCAT design, but dropped because both construction on both ships had already begun and the cost of modifying them to a CATOBAR configuration was unacceptable steep.

ShauryaT · Post by **ShauryaT** » 17 May 2016 06:13

Viv S wrote:
ShauryaT wrote:Lookup the conversion ratio from MWt to MWe for Russian designs.
The Russians don't have any electric drives on warships, let alone on submarines.

Not referring to electric drive it is the electrical power generated to drive the turbines.

Compare top speed for given tonnage for Arihant. 90 MWt is the proposal from BARC to power the SSN.
Its top speed has never been revealed. Top speed is primarily a function of its hydrodynamic design. And the design drivers there are acoustic.

Sure not. You have to do your own readings and sources for it and come to an understanding.

Also, that 75MW is like 75MW e (50,000 HP *2 gas turbines) to the shafts? that is huge (assuming that is the electrical conversion from thermal). The Akula 190MWt reactor provides only 29MWe. Also, did they not explore fitting the EMALS to the QE carriers and determined that the power requirements were at the edges and hence not viable.
The QE delivers 80 MWe to the propulsion. The Russians' limitations in terms of transmission (or miniaturization) don't necessarily apply to India.

You can believe what you want. Am not restarting the debate.

Viv S · Post by **Viv S** » 17 May 2016 06:36

ShauryaT wrote:Not referring to electric drive it is the electrical power generated to drive the turbines.

Do you know how much electric power their warships and/or submarines consume? Or how much power is delivered to their generators by the drive-train? If so, do share because I've seen nothing in the (English speaking) public domain.

Sure not. You have to do your own readings and sources for it and come to an understanding.

I don't know the top speed of the Seawolf or Virginia or Ohio or Vanguard or Triomphant classes. For good reason. Which is enough for me to understand that any figures circulating in public for the Arihant should be taken with a fistful of salt.

You can believe what you want. Am not restarting the debate.

Your wish. All I'm saying is that your statement ("Arihant reactor is a Russian design.. we are done with the debate on that") wasn't exactly the final word on the matter that your tone implied it was.

Cybaru · Post by **Cybaru** » 18 May 2016 01:51

Isn't 6.3 MVA roughly 6.3MW? for 4 catapults on average. Whether you go nuclear or not, you can always dump a small generator on the ship to generate electricity. It won't take any more than one container sized space for the actual generation unit.

NRao · Post by **NRao** » 25 May 2016 20:18

Sorry if already posted

US hard-sells nuclear powered carrier to India

member_28911 · Post by **member_28911** » 25 May 2016 20:57

Cybaru wrote:Isn't 6.3 MVA roughly 6.3MW? for 4 catapults on average. Whether you go nuclear or not, you can always dump a small generator on the ship to generate electricity. It won't take any more than one container sized space for the actual generation unit.

No. It depends on the input power factor as seen by the electrical generator.

Cosmo_R · Post by **Cosmo_R** » 25 May 2016 21:33

Of A1B reactors/ SHP and the like. No idea whether this is credible

http://analyseeverythingaround.blogspot ... ty-on.html

sudeepj · Post by **sudeepj** » 25 May 2016 21:53

Cybaru wrote:Isn't 6.3 MVA roughly 6.3MW? for 4 catapults on average. Whether you go nuclear or not, you can always dump a small generator on the ship to generate electricity. It won't take any more than one container sized space for the actual generation unit.

I am not sure what 'avg' means here, the cats need 6.3 MW over a period of 24 hours to launch the 100-200 launches they can do per day? or a 6.3 MW power generation capacity will allow you to do as many launches as you want?

Considering that if two carriers duke it out, and if other things are equal, the rate at which they launch and recover the planes is the key to who will win, a smaller generator will be the limiting factor in how many planes the carrier can put up in the air.

From a physics point of view, launching a 25 tonne plane (fully loaded Shornet or E2D) at 300kmph needs about:

0.5 x 25,000, (300 x 1000 / 3600)^2 = 87 Mega Joules of work to launch one plane.

Assume 25% efficiency from the transfer of power from the generator to the plane velocity to get around ~348 Mega Joules of work done by the generator. A genset rated at 3 MW max will need to work for ~116 seconds at max capacity to do this amount of work.

A DE generator from a locomotive can easily generate this much electricity.. Better still, have a few such locomotive generators to meet redundancy and surge requirements. Most ships have such generators for the 'hoteling' loads anyway. Not sure why nuclear is the only thing that is considered capable of launching planes using EMALs.

Pratyush · Post by **Pratyush** » 26 May 2016 06:08

Sudeep, the ship with better ISR support and escorts will win. Victory has nothing to with the numbers of launches and recoveries.

vina · Post by **vina** » 26 May 2016 07:56

The Russians don't have any electric drives on warships, let alone on submarines.

It is not about electric drives, but the fact that a nuclear reactor generates heat (say 90MW Thermal), which needs to be converted into mechanical energy via a steam turbine (shaft power), which can directly drive a propeller and other accessories. So basically, that will have a 30% efficiency (at max) in a land based nuclear power plant with no size constraints, and in a minaturized sea based one you will have 15% to 20% efficiency (at best). So you are looking at 13 Mw to 18Mw shaft power at best, if the ship is electrically driven, what you will have is approx 90% of shaft hp and you will get roughly 11 to 16 Mwe .

JTull · Post by **JTull** » 26 May 2016 08:16

What is the source of this assumption of only 2 CATs in IAC-II? There are two lines for take off - one for the aircraft stowed near the bow and one from waist. Each must have a second CAT for backup. Otherwise, if one breaks down, the carrier deck would just be towing aircraft around in an unusual game of musical chairs.

Philip · Post by **Philip** » 26 May 2016 10:56

The cost of an N-powered EMALS CV with JSF fighters will beggar not just the IN but the defence budget.It would also mean putting so much money into just one basket. When elderly Swedish diesel subs can "sink" US N-CVs regularly in exercises today,carrier survivability for any navy in the context of BM strikes,LRCMs and lurking quiet subs,suicide UUVs,in the presetn and future is going to be a tough task.

Yes, the USN would love India to possess an "American" nuclear powered carrier,paid for by India,but in essence nothing but a Yanqui "benami" carrier for free,which it will use to fight China with!

ShauryaT · Post by **ShauryaT** » 26 May 2016 19:08

vina wrote:
The Russians don't have any electric drives on warships, let alone on submarines.
It is not about electric drives, but the fact that a nuclear reactor generates heat (say 90MW Thermal), which needs to be converted into mechanical energy via a steam turbine (shaft power), which can directly drive a propeller and other accessories. So basically, that will have a 30% efficiency (at max) in a land based nuclear power plant with no size constraints, and in a minaturized sea based one you will have 15% to 20% efficiency (at best). So you are looking at 13 Mw to 18Mw shaft power at best, if the ship is electrically driven, what you will have is approx 90% of shaft hp and you will get roughly 11 to 16 Mwe .

Correct and as a rough translation for the two massive 550 MW each reactors on the Nimitz, it provides about 200MW of power to the Nimitz, including about half of it to the shafts. The new Ford class reactors are estimated at about 700 MW each and has a better thermal to electric conversion.

Now for someone to say, we will put two Arihant reactors uprated to 90MWt to drive an EMALS equipped 65K ship does not pass the smell test. We will need a new reactor design is my understanding.

Cybaru · Post by **Cybaru** » 26 May 2016 19:12

I don't think the EMALS energy requirements are that huge. 10 banks of super capacitors of 121MJ's will provide sufficient buffer even against a lower MW gen set for charging. The old paper that brar posted hinted at flywheel for quick discharge of 121MJs for one launch. That should not be a reason to go with a nuclear design.

sudeepj · Post by **sudeepj** » 26 May 2016 20:52

Pratyush wrote:Sudeep, the ship with better ISR support and escorts will win. Victory has nothing to with the numbers of launches and recoveries.

Which is why I said, other things being equal.

Obviously, an aircraft on deck is completely useless until its armed, fueled and launched.. If a carrier can 'surge launch' all of its fighter/attack wing into the air, say in 30 minutes, while the opposition can only launch half of its aircraft, the carrier group with the greater number of fighter/attack aircraft flying will be at a huge advantage.

While this scenario may appear far fetched today based on the history of the past few decades, the reality is, as Adm. Arun Prakash puts it, 'the carrier has operated in a fairly benign environment post WW II'. We have not seen two navies, each centered around CBGs facing each other in the past 60 years, since Midway.

At Midway, the key things that influenced the outcome was:
a. Better intelligence efforts. (Deducing the target of the Japanese flotilla using intelligence/counter intelligence efforts)
b. Better scouting capability. (The Japanese carriers sent much fewer scout planes compared to the American fleet)
c. Japanese not being able to launch their fighters. (Due to the fog of war, the Japanese fleet could not launch their fighter/attack aircrafts because of confusion about arming them with torps/bombs..)
c. Better fighters. (American fighters were much better machines and the pilots were trained better)

Today, a CBG vs CBG battle will be decided on similar factors and other things being equal, capability to 'surge launch' greater numbers of fighters will be important in a CBG vs CBG or a CBG vs shore based airbase matchup. Not so much if you are hammering Gaddafi or ISIS..

sudeepj · Post by **sudeepj** » 26 May 2016 20:56

Cybaru wrote:I don't think the EMALS energy requirements are that huge. 10 banks of super capacitors of 121MJ's will provide sufficient buffer even against a lower MW gen set for charging. The old paper that brar posted hinted at flywheel for quick discharge of 121MJs for one launch. That should not be a reason to go with a nuclear design.

You may be on to something.. Having visited the engine room of a relatively modern 8000 TEU container ship, I saw 4 DE gensets of 2 MW each. Two were for hotel loads and to supply electricity to the refrigerated containers, while two were for operating the bow/lateral thrusters. I can't imagine a warship not having similar or even greater requirements.

One could perhaps intelligently design a carrier so some of the hotelling loads/bow thrusters output be rerouted to the EMALs energy bank in times of emergency.

sudeepj · Post by **sudeepj** » 26 May 2016 21:02

Philip wrote:The cost of an N-powered EMALS CV with JSF fighters will beggar not just the IN but the defence budget.It would also mean putting so much money into just one basket. When elderly Swedish diesel subs can "sink" US N-CVs regularly in exercises today,carrier survivability for any navy in the context of BM strikes,LRCMs and lurking quiet subs,suicide UUVs,in the presetn and future is going to be a tough task.

Again, the same nonsense. All of the above applies equally to a small carrier such as the Gorshkov or the Vikrant. Further, the USN needs/wants to deploy its carriers in the persian gulf and the Taiwan straits. Very restricted spaces where a DE sub can set up an ambush.

An Indian CBG would operate in the open ocean, at least a few hundred kms away from the Pak coast and somewhere around Andamans if it were to face a Chinese flotilla.

Hoping that a CBG moving at 30 knots, with tens of ASW choppers and fixed wing planes, can be hunted by a DE sub crawling at two knots in the open ocean is a Vodka induced hallucination.

Philip wrote:Yes, the USN would love India to possess an "American" nuclear powered carrier,paid for by India,but in essence nothing but a Yanqui "benami" carrier for free,which it will use to fight China with!

Is the Vikrant a benami Russian carrier because it flies the Mig 29?

Vivek K · Post by **Vivek K** » 26 May 2016 21:44

sudeepj wrote: ....

Philip wrote:Yes, the USN would love India to possess an "American" nuclear powered carrier,paid for by India,but in essence nothing but a Yanqui "benami" carrier for free,which it will use to fight China with!

Is the Vikrant a benami Russian carrier because it flies the Mig 29?

KrishnaK · Post by **KrishnaK** » 26 May 2016 22:15

Pratyush wrote:Sudeep, the ship with better ISR support and escorts will win. Victory has nothing to with the numbers of launches and recoveries.

Victory depends on the goals set out. The whole point of a carrier is to put planes in the air. Sortie generation rates have everything to do with the amount of force those planes can bring to bear, given their endurance and payloads are not infinite.

kit · Post by **kit** » 26 May 2016 23:38

just because the NRI kid was born American doesn't mean he wont behave as an Indian

vishvak · Post by **vishvak** » 27 May 2016 01:51

Folks who do consider cost of Russian carrier purchase would surely consider the same exact strictures for one super carrier buy from USA, too. Going by a lot of new tech on a new platform may increase the risk w.r.t. not exactly working as well as for USA.

NRao · Post by **NRao** » 27 May 2016 02:59

The challenge is scaling a relatively new technology to handle the required weights and power. EMALS motor generator weighs over 80,000 pounds, and is 13.5 feet long, almost 11 feet wide and almost 7 feet tall. It’s designed to deliver up to 60 megajoules of electricity, and 60 megawatts at its peak. In the 3 seconds it takes to launch a Navy aircraft, that amount of power could handle 12,000 homes. This motor generator is part of a suite of equipment called the Energy Storage Subsystem, which includes the motor generator, the generator control tower and the stored energy exciter power supply. The new Gerald R. Ford Class carriers will require 12 of each.

The related Advanced Arresting Gear (AAG) sub-program will replace the current Mk 7 hydraulic system used to provide the requisite combination of plane-slowing firmness and necessary flexibility to the carriers’ arresting wires. The winning AAG design replaces the mechanical hydraulic ram with rotary engines, using energy-absorbing water turbines and a large induction motor to provide fine control of the arresting forces. AAG is intended to allow successful landings with heavier aircraft, reduce manning and maintenance, and add capabilities like self-diagnosis and maintenance alerts. It will eventually be fitted to all existing Nimitz class aircraft carriers, as well as the new Gerald R. Ford class.

Just a data point. Not one in support of nuclear powered carrier.

sudeepj · Post by **sudeepj** » 27 May 2016 21:02

NRao wrote:
The challenge is scaling a relatively new technology to handle the required weights and power. EMALS motor generator weighs over 80,000 pounds, and is 13.5 feet long, almost 11 feet wide and almost 7 feet tall. It’s designed to deliver up to 60 megajoules of electricity, and 60 megawatts at its peak. In the 3 seconds it takes to launch a Navy aircraft, that amount of power could handle 12,000 homes. This motor generator is part of a suite of equipment called the Energy Storage Subsystem, which includes the motor generator, the generator control tower and the stored energy exciter power supply. The new Gerald R. Ford Class carriers will require 12 of each.

Just wanted to add, that this is the **energy storage subsystem**, i.e. the ultra capacitor or whatever you want to call it. Its the part that is discharging the huge jolt of power needed in the 3 seconds it takes to launch the plane. The DE generator can be much smaller, and putter away in the background reloading this machine with the kinetic energy which will then be transferred to the plane in 3 seconds.

Three of these needed for each cat.

Philip · Post by **Philip** » 28 May 2016 12:59

The diff is that the Vik-A does not come with logistics agreements,and other strings,cord,that the US wants us to sign on to! Russian warships rarely visit Indian ports and have little global agenda other than protecting their interests,primarily defending their country.A massive carrier based upon a USN supercarrier design would be enormously beholden to US intrusive inspections,etc.,especially if JSF aircraft are aboard. Secondly,the USN is clearly drawing the IN into a military alliance against China which we would be well advised to stay clearly away from,and avoid getting drawn into an unnecessary conflict with one of our two mortal enemies.

We should show the same diplomatic-cum-military independence with Vietnam,as we've just shown with Iran and base some of our naval assets in Viet ports and airfields,just as the Chinese are acquiring at Gwadar. We need to supply the Viets with a range of desi missiles for strike and defence,and set up a "research" N-reactor which will allow the Viets to make their own bomb one day. This will hugely assist us in countering any mischief from the PRC through a presence in the Indo-Chinaa Sea,with bilateral mil-agreements retaining our independence and sovereignty of action, rather than joining a power-bloc whose primary interests may differ from ours and needlessly drag us into one of their conflicts.

The IN which has its unsinkable landmass and strategically located island territories can base any number of LRMPs and LR strike aircraft where it chooses. Our agreements with Mauritius and Seychlles should be pursued further with other littoral nations.This will allow us to sanitise the IOR with greater reach and ease.What we lack is a large lethal sub fleet ,where we should put our hard cash into instead of supercarrier ambitions. We would be able to afford the entire lot of 6 SSNs for the price of one supercarrier and its air contingent and have extra cash on hand. Who would you put your money on,the carrier or the nuclear-powered wolf pack?

PS:The weaponload of a modern SSGN/SSN is enormous. An Akula carries 40+ weapons.US subs launched hundreds of Tomahawk missiles in the recent ME conflicts,esp in Libya.It uses its supercarriers
primarily for power projection,floating airfields,in support of its ground troops as in the Gulf Wars,etc. India has no "expeditionary warfare" role or ambitions other than helping in the security of the aforementioned littoral island nations. The planned 4 amphibs if made large enough to operate STOVL aircraft in a multi-role design,could assist hugely in providing air cover and ASW screens for surface task forces,apart from deploying marines to the A&N command to forestall any invasion plans from extraneous forces.Saturation attacks of supersonic/hypersonic missiles against a CBG would be virtually impossible to deter. In fact once detected and tracked by Indian maritime sats,a CBG would be vulnerable to any BM strike too.

PPS:Let's take a long hard look at China and its ambitions.Its primary goal is recovering Taiwan at any cost,for which it is willing to play the long game.The Chinese think in centuries.Look how they got back Hong Kong. If one examines its mil buildup,esp that of its navy,it wants any invasion of Taiwan to forestall any movement of US task forces,esp CVs,which one may remember many years ago steamed through the Taiwan Straits at a time of crisis showing the upturned finger to the PRC! That cat by the USN saw the PLAN acquire Russian Sov. DDGs,with supersonic Moskit SSMs.I seriously doubt any USN CBG will do it again at a time of acute crisis.

It is further building up its amphib capability not just for any invasion of Taiwan but also for securing the atolls in the Indo-China Sea which it has grabbed by force.latest reports now say that due to intrusive USN patrols in the ICS ,esp in the air,snooping around Hainan,the PLAN is to send its SSBNs for the first time ever into the pacific on forward offensive patrols with its MIRV BMs aimed at the US landmass. The US is trying to counter China's landgrabbing in the ICS and support its allies with increased naval activity including a return to the Phillipines.

The Chinese planned base at Gwadar is meant to provide an operational enclave for its naval/air assets to safeguard its energy supplies in any such spat with the US. It would be exceptionally foolhardy for it to engage militarily with India in the Himalayas where we are much stronger today,which will also force us to consider asymmetric action against PRC maritime interests in the IOR,where we are far stronger than the PLAN. This is why its silk route.land/rail links through Tibet,Pak,etc.,are meant to offset its geographic vulnerabilities,but even these can be disrupted and destroyed by a powerful IAF.

Cybaru · Post by **Cybaru** » 28 May 2016 23:49

NRao wrote:
The challenge is scaling a relatively new technology to handle the required weights and power. EMALS motor generator weighs over 80,000 pounds, and is 13.5 feet long, almost 11 feet wide and almost 7 feet tall. It’s designed to deliver up to 60 megajoules of electricity, and 60 megawatts at its peak. In the 3 seconds it takes to launch a Navy aircraft, that amount of power could handle 12,000 homes. This motor generator is part of a suite of equipment called the Energy Storage Subsystem, which includes the motor generator, the generator control tower and the stored energy exciter power supply. The new Gerald R. Ford Class carriers will require 12 of each.
Just a data point. Not one in support of nuclear powered carrier.

Perhaps someone can correct my calculations.

You need about 103 barrels of oil to create 60 MW for an hour. Now if you need to power 12000 houses, you need a whole lot of fuel. Far more than what you can carry on CVN. That quote above on powering 12000 homes may only be correct for about 3 seconds. Not much use IMO.

Flywheels can be heavy and are mechanical energy storage and transfer devices. They do transfer energy really really fast unlike batteries and generator sets. And yes they do take up a large amount of space due to all the physical gearing and mechanics of storing energy in them. Ultra capacitors unlike regular batteries have extremely high discharge rates and cycle rates, they do take a lot less space. I suspect that all future CVN's being produced will use that over flywheels. This also means less damping equipment will be required etc to house these.

Roughly you need 4 gallons of energy per launch if read this correctly. https://en.wikipedia.org/wiki/Electroma ... nch_System

Energy storage subsystem[edit]
During a launch, the induction motor requires a large surge of electric power that exceeds what the ship's own continuous power source can provide. As of 1994, the EMALS energy-storage system design accommodates this by drawing power from the ship during its 45-second recharge period and storing the energy kinetically using the rotors of four disk alternators; the system then releases that energy (up to 484 MJ) in 2–3 seconds.[4] Each rotor delivers up to 121 MJ (34 kWh) from 6400 rpm (approximately one gasoline gallon equivalent) and can be recharged within 45 seconds of a launch; this is faster than steam catapults.[2] A max launch using 121 MJ of energy from each disk alternator slows the rotors from 6400 rpm to 5205 rpm.[4][5]

NRao · Post by **NRao** » 31 May 2016 04:19

Defence Ministry eyeing optimal resource utilisation for more submarines & advanced frigates

The defence ministry is doing a rethink on a prohibitively expensive naval programme for a futuristic aircraft carrier and is evaluating options for more optimal utilisation of resources for other critical purchases — like submarines and advanced frigates .

Officials have confirmed to ET that the Navy's plan for a 65,000 ton nuclear-powered aircraft carrier to be fitted with an American catapult system is not likely to get financial clearances soon as the ministry was looking at other options. While a detailed project report for the carrier is ongoing and the Indo-US Joint Working Group on Aircraft Carrier Technology Cooperation (JWGACTC) is in place, officials say that the next step involving release of more funds could be deferred.

Defence minister Manohar Parrikar when asked told ET that he could not comment on the matter as he had not taken a decision on the project as of now. Navy officials said that they have not received information on the future of the plan yet.

A reason for the rethink is the massive cost involved in the new-age aircraft carrier. By conservative estimates, the cost of construction of the carrier itself, without the aircraft, would exceed Rs 70,000 crore. The high cost is primarily due to the integration of the nuclear plant as well as the American electromagnetic aircraft launch system (EMALS) being planned.

As of now, the defence ministry has allocated Rs30 crore to the project after an approval by the highpowered defence acquisition committee last year. Officials have told ET that out of this, only Rs 2 crore has been released in this financial year for the project.

With other critical naval projects requiring attention — including two lines of indigenous nuclear powered submarines — a line of thinking within the defence ministry is that allocating huge resources to a single platform would not be prudent.

"The aircraft carrier itself is expensive and also requires a number of warships and platforms around it to operate at sea. We also have other pressing needs of the Navy to consider," a defence ministry official said.

Read more at:
http://economictimes.indiatimes.com/art ... aign=cppst

MoD officials. Need to hear from political wing. And service.

However, may be finances force more Vikrants.

ShauryaT · Post by **ShauryaT** » 31 May 2016 04:51

>>By conservative estimates, the cost of construction of the carrier itself, without the aircraft, would exceed Rs 70,000 crore.

My estimate was $10 billion!! and I was wrong. I was including the aircraft cost in my estimate. All those who thought this was not as expensive, please take note!!

Suresh S · Post by **Suresh S** » 31 May 2016 05:05

like your post above philip. if India does just the opposite of what the US wants us to do then we can not go wrong.

NRao · Post by **NRao** » 31 May 2016 05:32

I would wait till MP speaks.

Here on out it is a pure political decision. The broad technical calls seems to have come in. And, if only 2 of 39 crores sanctioned have actually been a allocated, then there is a huge gap for sure. Even another carrier could be in jeopardy - which is why he perhaps has titled it that.

BTW, nothing to do with US. Everything requested, including EMSLS, Aid IN based request. Last year IN issued a letter of request for it. And the joint working group is also Indian request.

I am betting there is a political will.

Cybaru · Post by **Cybaru** » 31 May 2016 05:33

NRao wrote:Defence Ministry eyeing optimal resource utilisation for more submarines & advanced frigates

The defence ministry is doing a rethink on a prohibitively expensive naval programme for a futuristic aircraft carrier and is evaluating options for more optimal utilisation of resources for other critical purchases — like submarines and advanced frigates .

Officials have confirmed to ET that the Navy's plan for a 65,000 ton nuclear-powered aircraft carrier to be fitted with an American catapult system is not likely to get financial clearances soon as the ministry was looking at other options. While a detailed project report for the carrier is ongoing and the Indo-US Joint Working Group on Aircraft Carrier Technology Cooperation (JWGACTC) is in place, officials say that the next step involving release of more funds could be deferred.

Defence minister Manohar Parrikar when asked told ET that he could not comment on the matter as he had not taken a decision on the project as of now. Navy officials said that they have not received information on the future of the plan yet.

A reason for the rethink is the massive cost involved in the new-age aircraft carrier. By conservative estimates, the cost of construction of the carrier itself, without the aircraft, would exceed Rs 70,000 crore. The high cost is primarily due to the integration of the nuclear plant as well as the American electromagnetic aircraft launch system (EMALS) being planned.

As of now, the defence ministry has allocated Rs30 crore to the project after an approval by the highpowered defence acquisition committee last year. Officials have told ET that out of this, only Rs 2 crore has been released in this financial year for the project.

With other critical naval projects requiring attention — including two lines of indigenous nuclear powered submarines — a line of thinking within the defence ministry is that allocating huge resources to a single platform would not be prudent.

"The aircraft carrier itself is expensive and also requires a number of warships and platforms around it to operate at sea. We also have other pressing needs of the Navy to consider," a defence ministry official said.

Read more at:
http://economictimes.indiatimes.com/art ... aign=cppst

MoD officials. Need to hear from political wing. And service.

However, may be finances force more Vikrants.

I think putting money in submarine fleet forces the enemy to put lots of money into ASW. Which is a very hard thing to do as no amount is good enough. This asymmetric method gives a huge edge to the country that has a bigger submarine force. Plus there is only so much money to go around. We have to contain costs somewhere and you never get rid of the replenishment boats and they are much much cheaper than the nuke gens.

A scaled up 65k conventional boat will serve our purposes equally well. They could still get cats/emals on it. Anyways out of a 50 year life of nuclear cvn, they will end up 16 years in the docks refueling and going through usual tests to ensure the nuclear plants work efficiently and safely.

Singha · Post by **Singha** » 31 May 2016 08:23

unless the economy can absorb the cost and build a fleet of 4 such CVN/CV @ 1 every 4 years delivery for 3 to act in concert as a 'strike' carrier, it carries no great advantage over the Vikky in the arabian sea / bay of bengal theater as land based ASW and fighters will be available for support.

1 single example will be a useless costly paperweight for photo ops with visiting american CVNs and touting 'interoperability' - it cannot remotely hope to get into harms way in south china sea and survive against PLAN+PLANAF - even a 3-4 carrier nimitz class force with 300-400 planes will call on land based tankers, rivet joints, F22/F15, B1, SSNs for support to wage a fight in such waters and we have no such backing line of shore bases and assets over there.

so lets invest in 6-10 SSNs first and get them into service..atleast packs some real teeth to get in and out of the east asian seas.

ideally we could do both, but since we cannot, SSNs must be #1 to #6 priority

we need to be churning out SSNs and "large ASW/AAW DDG hulls" by the early 2020s as Cheen already does today

Yagnasri · Post by **Yagnasri** » 31 May 2016 08:32

Long range bombers like bears with anti-ship capability will give us the control of Indian Ocean to a large extent against China unless China manages to fields carrier groups here in our backyard. That can be countered by a significant number of SSNs Even MKI with mid-air refueling covers large areas. Large base in Andamans and some presence in Vietnam will help us to cover most of the Indo-china seas. With this present model of 3-4 40k carriers sounds ok for our purpose under the current budgetary constraints.

Singha · Post by **Singha** » 31 May 2016 09:55

also it is a well hidden 'secret' that USN tanker assets (if any) are completely inadequate to cover the needs of their CVN air wings on a sustained mission. they always field and deploy ANG/USAF tankers enmasse for this purpose using drogue refueling units (usaf fighters use the probe method) .. all these backline assets are always spoken for whenever brar_w brings up his east china sea battle scenarios.
without them, not even the nimitz class assets will make a dent on the hornets nest.

so its not as if a 65000t carrier without local supporting assets from land is going to shake anyone up.

Cain Marko · Post by **Cain Marko** » 31 May 2016 12:01

Singha wrote:unless the economy can absorb the cost and build a fleet of 4 such CVN/CV @ 1 every 4 years delivery for 3 to act in concert as a 'strike' carrier, it carries no great advantage over the Vikky in the arabian sea / bay of bengal theater as land based ASW and fighters will be available for support.

1 single example will be a useless costly paperweight for photo ops with visiting american CVNs and touting 'interoperability' - it cannot remotely hope to get into harms way in south china sea and survive against PLAN+PLANAF - even a 3-4 carrier nimitz class force with 300-400 planes will call on land based tankers, rivet joints, F22/F15, B1, SSNs for support to wage a fight in such waters and we have no such backing line of shore bases and assets over there.

so lets invest in 6-10 SSNs first and get them into service..atleast packs some real teeth to get in and out of the east asian seas.

ideally we could do both, but since we cannot, SSNs must be #1 to #6 priority

we need to be churning out SSNs and "large ASW/AAW DDG hulls" by the early 2020s as Cheen already does today

Yeah, can't get the idea behind a single super carrier....Arihant multirole class ssn/ssgn it's needed along with 12 more p8, and 12 mrmpa. would be great too see the shourya turn to anti carrier duty vs plan along with a host of asw ffgs..with bmos and nirbhay in a uvls setup. Fixing the helo gap has to be a priority. Don't see the need for too many ddg types either...expensive. Turning AN into a solid fortress with two flanker sqds with bmos capability might be useful..

BTW, would love to get TSarkarjis opinion on this...super carrier ambition