Aircraft Carriers II (Closed to posting)

delft said:

Thank you. As an engineer I would want to estimate what it would cost to provide air power at sea, at what reliability, using aircraft carriers with two reactors or with one reactor and GT get home power. Would a carrier with half its power lost still be able to achieve the speed necessary to launch and recover aircraft?
What you said about a higher pressure steam system for the cats makes using EM cats seem even more attractive.

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That's why you have a whole division in most big military establishments dedicated to what is called "Warfare Analysis" or "Operations Research Analysis" dedicated to answering these sorts of questions. They will use statistical analysis techniques taken from physics, engineering and economics to model aspects of warfare (example, the most effective placement of mines in a minefield, or the optimum size of ASW air bases and their distance from each other considering the optimum length of patrols before boredom makes further patrol futile, the optimum period between maintenance evolutions which in turn drives the optimum size of the maintenance shops, etc.) That was one of the big innovations of WWII and we can credit the Brits with this, hiring scientists from multiple disciplines to run these studies.
Today, every new or proposed system will be modeled by operations research analysts in multiple scenarios, along with the costs to develop, procure, operate and maintain it afterward.
Your observation about EMALS vs steam cats is spot on. If you look back, you will see the French version of the CVF, before it was cancelled, had to be larger in part to accommodate the boilers necessary for that versions steam cats. The British version will be smaller, but using EMALS, not so much space is lost in the switch from STOVL to CATOBAR. Those ships are gas turbine so there is no propulsion steam available for catapults, but even on the Midway on display in San Diego you can see the big boilers for the bow cats in a space forward of the hanger bay.

I have another question. Battle ships had bulges, the latter ones "internal" bulges, to limit the damage cause by torpedo hits to vital areas. I suppose that aircraft carriers, at least the larger ones, have similar internal bulges alongside the propulsion plant and the ordnance stores. An aircraft carrier with a tricat configuration, similar to that Littoral Combat Ship, can use its side hulls as protection against shallow running torpedo's. The need for protection against mines and deeper running torpedo's remains the same. Such an aircraft carrier might have to pay for that advantage with increased structural weight for the connection of the hulls, but its flight deck and hangar will be larger and have a more convenient shape for a given LOA.
Might this be a good configuration for smaller aircraft carriers?

delft said:

I have another question. Battle ships had bulges, the latter ones "internal" bulges, to limit the damage cause by torpedo hits to vital areas. I suppose that aircraft carriers, at least the larger ones, have similar internal bulges alongside the propulsion plant and the ordnance stores. An aircraft carrier with a tricat configuration, similar to that Littoral Combat Ship, can use its side hulls as protection against shallow running torpedo's. The need for protection against mines and deeper running torpedo's remains the same. Such an aircraft carrier might have to pay for that advantage with increased structural weight for the connection of the hulls, but its flight deck and hangar will be larger and have a more convenient shape for a given LOA.
Might this be a good configuration for smaller aircraft carriers?

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This was already discussed in this thread or another.

http://www.sinodefenceforum.com/navy/ideal-chinese-carrier-thread-3-2777.html

The type hulls you describe would limit the amount of fuel, weapons and supplies a carrier could store. Where as most of the supplies are now carried below the water line.

bd popeye said:

^^Have you ever heard of an USN CVN not making a commitment because of reactor failure? I have not.

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Popeye...here's some good info for you about the upcoming mod for the Russian Kuznetsov...sounds like a hugel SLEP.


It's from:

The upcoming large-scale modernization was motivated by the need to eliminate the ship's inherent drawbacks and to repair some of her units. Plans for docking the ship in 2010-2012 were discussed more frequently and have now been confirmed.

Although it is hard to assess the revamped carrier's specifications, her future appearance can be predicted on the basis of available reports.

First of all, the defective propulsion unit comprising steam turbines and turbo-pressurized boilers will be replaced either with a gas-turbine or nuclear propulsion unit.

The ship's 3M45 P-700 Granit (SS-N-19 Shipwreck) anti-ship cruise-missile launchers will be dismantled, and her internal layout changed. Consequently, the hangar area will be expanded to 4,500-5,000 sq. m. for storing additional fixed-wing aircraft.

The Admiral Kuznetsov's air defenses will be strengthened by replacing 3K95 Kinzhal (SA-N-9 Gauntlet) missiles with a multi-role naval system featuring 80-120 new-generation and medium-range surface-to-air missiles (SAMs).

Moreover, 4-6 Pantsir-S1 (SA-22 Greyhound) combined short to medium-range SAM and anti-aircraft artillery weapons systems will be installed.

The new weapons systems will feature state-of-the-art radio-electronic equipment, probably including the standard Sigma combat information and control system, due to be installed on all new generation Russian warships. The system facilitates unprecedentedly effective cooperation between task force elements.

The carrier will also receive aircraft catapults, a logical option. Considering the fact that her ski-jump will remain intact, one or two catapults can be located on the angled flight deck.

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Either gas turbine or nuc engines planned to be installed. That's huge. Also, cats on the angle deck, just as we have discussed for the Chinese Varyag (or Shilang).

Interesting.

Jeff.. sound ambitious.. However the Russians keep announcing different plans to build CVs.. then they draw back. Once again we will have to use the wait and see approach on this one.

What's the time frame on this Russian SLEP??

Can you please link me to any previous SDF threads/discussions on the Russian Ulyanovsk class carrier as i'm having trouble finding them.Thanks in advance.

zoom said:

Can you please link me to any previous SDF threads/discussions on the Russian Ulyanovsk class carrier as i'm having trouble finding them.Thanks in advance.

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Sure thing..

Soviet Carrier Development

Only VIP members can post in the thread above.

bd popeye said:

This was already discussed in this thread or another.

http://www.sinodefenceforum.com/navy/ideal-chinese-carrier-thread-3-2777.html

The type hulls you describe would limit the amount of fuel, weapons and supplies a carrier could store. Where as most of the supplies are now carried below the water line.

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The tricat carrier you refer to is certainly fantastic. I have looked around a little in that thread and I saw plenty of reasons to investigate alternative configurations, including tricat. There is the argument, that in more balanced military situations more smaller carriers are advantagious. And that on CATOBAR QE carriers the cats intrude in the landing area. I'll think further.

I have a friend of mine that goes to our church who is working on electro magnetic catapults for the FORD class ships. It almost didn't go through because some in the current administration thought it was too expensive. Thankfully it went through. He is having a blast! I can't wait to see these systems launching our pilots into action.
Plus is there any photo's of progress on India's latest two carriers. I am talking within the last month. Same thing for Sao Paulo. She is out of refit if I am not mistaken.

delft said:

The tricat carrier you refer to is certainly fantastic. I have looked around a little in that thread and I saw plenty of reasons to investigate alternative configurations, including tricat. There is the argument, that in more balanced military situations more smaller carriers are advantagious. And that on CATOBAR QE carriers the cats intrude in the landing area. I'll think further.

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The flight deck configuration for the CVF was dictated in part by the exhausts for the gas turbine propulsion and the original intent make the ship a STOVL design. There used to be a Royal Navy study available on line showing the daily sortie rates for both a STOVL and CATOBAR ship, and the STOVL design had a substantially higher daily sortie rate.
Ideally the island should be well aft but the necessity of two big exhaust trunks for the gas turbine power plant dictated either two small islands or one very big one. For the STOVL design, two small islands made more sense, and the sponson below the forward island keeps a lot water out of the forward elevator and hanger bay door. I have to imagine they are now regretting that design choice as the similarly sized Midway has a much more logical flight deck and elevator arrangement than the CVF with cats and A-gear.
Still, this buys the Brits the option of flying heavier aircraft in the future, cross decking with the USN and now they can buy those E-2D's they want.
Regarding size of the carrier; the USN has performed multiple studies of carrier size and found no advantage to building smaller carriers. To launch a fully loaded F-14 or F/A-18E/F, or an E-2D if you want to keep a margin for a single engine failure on take off, you need the full 95 meter long C-13 cat. The French found out with the CdG that a smaller flight deck and shorter cats didn't work so well for them in all wind and sea conditions. Their version of the CVF, had it not been cancelled, was going to be 72,000 tons, the size of a Kitty Hawk, and run the full 95 meter long version of the C-13 cat. Big hulls work better in all seas and are faster. There are times when a Nimitz can sail down wind and still have relative wind over the deck. That speed buys them some operational flexibility not present on earlier carriers.
Small carriers make sense only if they are STOVL like a Cavour or Invincible, but you loose the ability to fly heavy strike or to fly an AEW aircraft until someone figures out how to incorporate the necessary radars and processing on a tilt rotor.