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Post by oldpop2000 on Jan 15, 2015 7:49:43 GMT -6
This link shows thrust to weight ratios for many different aircraft and the formula for calculating it. We should adopt this in any of our discussions.
defenceforumindia.com/thrust-to-weight-ratio-fighter-plane-460
Update: I began to think of other problems that have to be addressed with ski ramps. One of them is the weight transfer to the main landing gears as the aircraft enters the ramp. This will require some real off line testing and beefing up of the main wing structure and attachment point of the wings to the fuselage. This will, of course, add weight. Another issue is weapons physical clearance of the minimum clearance distances of the ramp. Flat tires and bad struts could result in total elimination of the ramp and now the main launch point of the carrier is out of service. Here's another question I have with ski ramps and with carrier design in general - wind over the bow. Historically, carriers have been fast ships. Not just because you want to get from one place to another quickly, but because every knot of wind over the bow helps get your birds in and out of the air in an easier fashion. The fleet carrier classes of WWII all had top speeds of 30 knots or better, and even though the aircraft they were launching were prop birds much lighter than modern carrier aircraft they still needed catapult launches on occasion for an extra push. The US supercarriers have all had top speeds of over 30 knots; so did the British Audacious-class and the French Clemenceau-class. Now if you look at some other modern carriers, they're slower than their WWII ancestors. The Charles de Gaulle was only designed to make 27 knots, and early on she was unable to make her design speed due to propeller issues. The Queen Elizabeths are listed with a design speed "in excess of 25 knots." The Kuznetsov reportedly tops out at 29 knots. With the exception of the Charles de Gaulle, these ships lack catapults. The QEs are at least using STOVL aircraft, but the Kuznetsov and Liaoning are operating large, heavy CTOL jets. How much of a loss is that 5-10 knot reduction in speed when it comes to aircraft operations? One advantage of ski ramps is that they don't require wind over the deck. While catapults don't either, they still use it to gain an extra cushion of speed. You might find this interesting - navysite.de/cvn/flightdeck.htm#cat
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Post by steel selachian on Jan 15, 2015 18:24:29 GMT -6
They might not require it to get the plane in the air, but my question was how much of a dent the speed reduction (not to mention taking off towards the ramp, which might be acting as a windbreak) will put in the aircraft's range and payload. That can be critical. ARA Veinticinco de Mayo had steam cats, but in calm conditions and with a top speed of 24 knots she couldn't get loaded A-4Q Skyhawks off the flight deck during the Falklands War. That spoiled her chance to hit the British task force before being recalled in the wake of the General Belgrano sinking.
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Post by oldpop2000 on Jan 15, 2015 18:57:50 GMT -6
They might not require it to get the plane in the air, but my question was how much of a dent the speed reduction (not to mention taking off towards the ramp, which might be acting as a windbreak) will put in the aircraft's range and payload. That can be critical. ARA Veinticinco de Mayo had steam cats, but in calm conditions and with a top speed of 24 knots she couldn't get loaded A-4Q Skyhawks off the flight deck during the Falklands War. That spoiled her chance to hit the British task force before being recalled in the wake of the General Belgrano sinking. The loss in combat weight due to lack of WOD varies with the aircraft. For the AV-8, WOD could reduce the deck run by 350 feet. Testing showed that a ski jump assisted takeoff for an AV-8 was improved by 53% over a flat deck launch. This would allow an increase from 3000 lbs to 5,900 lbs. Tests were also conducted at Pax River for F-14A and F/A-18A using a catapult/Ramp Assisted Take off. There were 96 tests conducted. Most of the Defense Technical Information Service documents on ski ramp tests were done for the AV-8B. These tests were done about the 1970-1990 test frame so they are not recent. I will keep looking in that area. I like to use actual naval test documentation, not internet stuff. I trust the DTIC test data more.
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Post by oldpop2000 on Jan 16, 2015 18:39:12 GMT -6
Here are some general rules of thumb from a document on DTIC, on carrier size and capability.
• The more missions a carrier is to perform, the more aircraft it needs and the bigger the ship must be.
• The longer the range or heavier the payload of the aircraft, the more likely the carrier will need catapults and arrested recovery.
• The bigger the flight deck, the bigger the aircraft that can be operated. Also, the faster the carrier, the bigger the aircraft that can be operated. (Faster carriers require bigger propulsion spaces, so these factors are complementary.) Some missions are best performed by bigger aircraft.
• Strike is a long-range, heavy-load mission, as is aerial refueling.
• One pays a penalty for VTOL capability. Even if the design of the aircraft does not involve performance compromises, which is a big assumption, it still takes extra fuel to take off vertically, because “there’s no such thing as a free launch,” and there will be much more restrictive weight limits on what one can “bring back” on landing—unused ordnance may have to be jettisoned. VTOL is at best inefficient, and at worst affects overall combat capability.
• A large carrier is more efficient—that is, it carries more aircraft per ton of displacement and can handle planes on board better than a small carrier.
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Post by oldpop2000 on Jan 17, 2015 12:05:45 GMT -6
I wasn't sure where this quote and comments should be placed, but this post should work nicely. On this issue of the Chinese carrier and the US military response, here is a quote from the British Daily News on 10 March 1912. It concerns the recent furor over whether four dreadnoughts or eight should be built, due to information that Krupp was buying more nickel. Nickel was used in the manufacture of the large guns so it was assumed that the German Navy was building more dreadnoughts and battlecruisers than was originally thought. The whole story of this conflict between the Admiralty and the government itself is lengthy but this comment that I am quoting seems to be apropos for current issues. Does this sound familiar? Has anything really changed in the one hundred and three years since this comment was made? This can become political but let's stay in the arena of geostrategy. Is the military, specifically the Navy caucus using the new Chinese carrier threat as a boogie man to gain more carriers.
Realistically, the Chinese are a long way from deploying a carrier fleet. As I have stated, they have little or no experience in actual warfare with carriers. They might not even have developed a strategic plan or need for them, they just feel that to be a world power, you need carriers. The French, British and the US have them, so why not us.
Hope this discussion proves interesting.
Marder, Arthur (2014-06-19). From the Dreadnought to Scapa Flow: Volume 1: The Road to War 1904-1914 (Kindle Locations 4540-4543). Seaforth Publishing. Kindle Edition.
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Post by steel selachian on Jan 17, 2015 19:09:28 GMT -6
I agree that national prestige seems to be a big driver behind the PLAN's carrier program. I do not at present see the PLAN with a real drive to mirror the USN's far-flung carrier deployments; they're still trying to establish sea control over the First Island Chain (which is a ways off, carriers or no carriers).
I don't particularly see the PLAN carrier program as something being used by the Navy caucus to push for more carriers. From what I've seen, the Middle East troubles are more what's being highlighted; the argument is we should go back to 12 carrier groups and 12 amphib groups with one of each on station in the Med, IO, and Western Pacific at all times. With the current setup of 10 carriers and 9 big-deck amphibs, the argument is that the Med is going uncovered.
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Post by oldpop2000 on Jan 17, 2015 19:17:00 GMT -6
I agree that national prestige seems to be a big driver behind the PLAN's carrier program. I do not at present see the PLAN with a real drive to mirror the USN's far-flung carrier deployments; they're still trying to establish sea control over the First Island Chain (which is a ways off, carriers or no carriers). I don't particularly see the PLAN carrier program as something being used by the Navy caucus to push for more carriers. From what I've seen, the Middle East troubles are more what's being highlighted; the argument is we should go back to 12 carrier groups and 12 amphib groups with one of each on station in the Med, IO, and Western Pacific at all times. With the current setup of 10 carriers and 9 big-deck amphibs, the argument is that the Med is going uncovered. I think the USN is beginning to get restless about the Chinese weapons systems including the carriers.
FYI- www.gonavy.jp/CVLocation.html - Examine this list carefully at the bottom for the carriers that currently being built. It is these ships that are delayed that will be used by the Navy caucus and Defense Department, claiming that the Chinese carrier situation along with other nations and geostrategic considerations that need to be addressed and that prompt completion is required. You might see something over the next year or two about this in the news. There are currently three carriers that need to be expedited and the Defense Department might go for another two to be funded and built. Just my opinion. I don't want to get political, but it might depend on who is in the White House and controls Congress. That's all we should say.
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Post by steel selachian on Jan 19, 2015 16:00:29 GMT -6
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Post by oldpop2000 on Jan 20, 2015 8:45:16 GMT -6
Both are interesting articles. As to the second, the collapse of the Russian navy has been in the works for many moons. They are a land based power, not a maritime power despite their words to the contrary. They occupy Mackinder's heartland. None of their naval bases have direct access to the oceans and with the breakup, even their Black Sea ports are now reduced. They can exist without naval power.
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Post by kyle on Jan 20, 2015 16:34:03 GMT -6
I agree that national prestige seems to be a big driver behind the PLAN's carrier program. I do not at present see the PLAN with a real drive to mirror the USN's far-flung carrier deployments; they're still trying to establish sea control over the First Island Chain (which is a ways off, carriers or no carriers). I don't particularly see the PLAN carrier program as something being used by the Navy caucus to push for more carriers. From what I've seen, the Middle East troubles are more what's being highlighted; the argument is we should go back to 12 carrier groups and 12 amphib groups with one of each on station in the Med, IO, and Western Pacific at all times. With the current setup of 10 carriers and 9 big-deck amphibs, the argument is that the Med is going uncovered. I think the USN is beginning to get restless about the Chinese weapons systems including the carriers.
FYI- www.gonavy.jp/CVLocation.html - Examine this list carefully at the bottom for the carriers that currently being built. It is these ships that are delayed that will be used by the Navy caucus and Defense Department, claiming that the Chinese carrier situation along with other nations and geostrategic considerations that need to be addressed and that prompt completion is required. You might see something over the next year or two about this in the news. There are currently three carriers that need to be expedited and the Defense Department might go for another two to be funded and built. Just my opinion. I don't want to get political, but it might depend on who is in the White House and controls Congress. That's all we should say.
Until or unless China can deal with western submarines, their carrier(s) are only worth so much. To me the 1/2 punch the USN has is the carrier force and the submarine force. I look at pre-WW1 and the naval arms race between the U.K. and Germany and see some loose parallels today with the USN carrier force and the potential Chinese CV's. They are a long ways from a really capable CV that is a match for an US CVN, but they're learning.
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Post by oldpop2000 on Jan 20, 2015 17:05:00 GMT -6
I think the USN is beginning to get restless about the Chinese weapons systems including the carriers.
FYI- www.gonavy.jp/CVLocation.html - Examine this list carefully at the bottom for the carriers that currently being built. It is these ships that are delayed that will be used by the Navy caucus and Defense Department, claiming that the Chinese carrier situation along with other nations and geostrategic considerations that need to be addressed and that prompt completion is required. You might see something over the next year or two about this in the news. There are currently three carriers that need to be expedited and the Defense Department might go for another two to be funded and built. Just my opinion. I don't want to get political, but it might depend on who is in the White House and controls Congress. That's all we should say.
Until or unless China can deal with western submarines, their carrier(s) are only worth so much. To me the 1/2 punch the USN has is the carrier force and the submarine force. I look at pre-WW1 and the naval arms race between the U.K. and Germany and see some loose parallels today with the USN carrier force and the potential Chinese CV's. They are a long ways from a really capable CV that is a match for an US CVN, but they're learning. For the Chinese to deal adequately with our subs, they are going to have to develop a smaller, more capable helo. The new Z-18 is only suitable for the carrier weighing in at over 13 tons. They will also have to develop and deploy an airborne early warning aircraft like the E2C. For that they will need a catapult and arresting system, and they don't have that capability as yet. So, ASW for them, except for land based aircraft, is minimal. In fact, just protecting the carrier will be problematic. All of this really depends on the real purpose of the carriers. If they are just fleet protection, then fighters for BARCAP, helo's for ASW and AEW aircraft will be sufficient. However, they will probably still need cat's and arresting systems.
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Post by steel selachian on Jan 20, 2015 19:39:19 GMT -6
Again, it's also a matter of where they would deploy that carrier. Sustained combat operations away from home require either a very capable replenishment fleet or an extensive network of overseas bases. The PLAN is working on the former (not sure how good they are at it) and as far as I'm aware hasn't made concrete progress on the latter. So in the foreseeable future at least they'll have to fight on their home turf inside the First Island Chain. That doesn't preclude them from sending a carrier group farther abroad, but a) it won't be fighting on that trip, at least not for very long, and b) you'd better hope a major conflict doesn't break out in the Western Pacific while it's away. The Russians have the same issue; in order to deploy outside their home waters they have to pass through Western-controlled choke points and have no safe havens or resupply ports away from home. On that note: foxtrotalpha.jalopnik.com/stupid-move-navy-will-buy-v-22-ospreys-to-replace-its-1679559201medium.com/war-is-boring/navy-ospreys-could-do-more-than-haul-cargo-3d054985642d
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Post by oldpop2000 on Jan 20, 2015 19:53:55 GMT -6
Again, it's also a matter of where they would deploy that carrier. Sustained combat operations away from home require either a very capable replenishment fleet or an extensive network of overseas bases. The PLAN is working on the former (not sure how good they are at it) and as far as I'm aware hasn't made concrete progress on the latter. So in the foreseeable future at least they'll have to fight on their home turf inside the First Island Chain. That doesn't preclude them from sending a carrier group farther abroad, but a) it won't be fighting on that trip, at least not for very long, and b) you'd better hope a major conflict doesn't break out in the Western Pacific while it's away. The Russians have the same issue; in order to deploy outside their home waters they have to pass through Western-controlled choke points and have no safe havens or resupply ports away from home. On that note: foxtrotalpha.jalopnik.com/stupid-move-navy-will-buy-v-22-ospreys-to-replace-its-1679559201medium.com/war-is-boring/navy-ospreys-could-do-more-than-haul-cargo-3d054985642dI believe that the second of the two articles probably has it correct. The V-22 is much more versatile and has commonality with the Marine Air Wings. The C-2 Greyhound is common with the E2 in the fuselage and engines along with most of the flight controls and instruments. It's really just an oversized E2, but I think the V-22 over time will prove to be a good choice.
Here is a question the first article does not answer. Yes, the current COD can carry 5 tons of the supplies about 1500 miles. But the question is, how often does it really do that. In other words, does the Navy really need that amount of supplies delivered out to that distance. I suspect the Navy knows that it doesn't. It seems to me, that the requirements for the 1960's when the C-2 was designed and built, have changed. There might not be that requirement anymore, but a multipurpose transport and gunship might be more beneficial.
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Post by steel selachian on Jan 20, 2015 20:46:10 GMT -6
I was wondering that too - what exactly is being transported on the COD flights? It's not bombs or avgas, the main ingredients for sustained combat ops. Five tons a trip is not going to get you very far. Spare parts is one thing (in particular, much was being made of being able to transport F135 engines; they're too big to fit in the V-22 or C-2 cargo holds), but if you don't already have spares stocked on the carrier or AOE/AKE two COD airframes are only going to help in those limited-quantity "for want of a nail" supply situations.
As far as the utility of the V-22, the big one I can think of is TRAP missions. Currently, unless you're lucky enough to bail out close enough for an MH-60S to get to you, a CVW is dependent on Marine or AFSOC assets to get downed aircrews out of a pickle. Having a couple of possibly-armed V-22s available to the CVW means that the carrier can rescue its own guys without being dependent on an ESG or prepositioned Air Force assets. Not sure how well the V-22 would be able to do a rescue hoist for over-water retrievals, though. Back when I was doing Fleet Command scenarios I liked to put a pair of V-22s on my carriers, simulating them as either a Navy COD replacement or tag-along Marine or AFSOC aircraft. Made picking up downed aviators a LOT easier.
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Post by oldpop2000 on Jan 21, 2015 8:13:51 GMT -6
I was wondering that too - what exactly is being transported on the COD flights? It's not bombs or avgas, the main ingredients for sustained combat ops. Five tons a trip is not going to get you very far. Spare parts is one thing (in particular, much was being made of being able to transport F135 engines; they're too big to fit in the V-22 or C-2 cargo holds), but if you don't already have spares stocked on the carrier or AOE/AKE two COD airframes are only going to help in those limited-quantity "for want of a nail" supply situations. As far as the utility of the V-22, the big one I can think of is TRAP missions. Currently, unless you're lucky enough to bail out close enough for an MH-60S to get to you, a CVW is dependent on Marine or AFSOC assets to get downed aircrews out of a pickle. Having a couple of possibly-armed V-22s available to the CVW means that the carrier can rescue its own guys without being dependent on an ESG or prepositioned Air Force assets. Not sure how well the V-22 would be able to do a rescue hoist for over-water retrievals, though. Back when I was doing Fleet Command scenarios I liked to put a pair of V-22s on my carriers, simulating them as either a Navy COD replacement or tag-along Marine or AFSOC aircraft. Made picking up downed aviators a LOT easier. I don't know what the Navy actually carriers in those birds and how far. I know they carry engine parts, whole engines and afterburners. They carry special stores and parts, sometimes people and patients. Again, how far I don't know. The MV-22 can carry twice the load of the C-2 but not the distance. So it would seem that distance is the distinguishing feature that the argument is over. But the Navy will sort it out, and I believe that the multipurpose nature of the MV-22 is very attractive to them.
breakingdefense.com/2015/01/navy-decides-to-buy-v-22-ospreys-for-carrier-delivery/
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