What future for the Light Aircraft Carrier? in Aircraft Carriers Forum

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What future for the Light Aircraft Carrier?

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HK		#61	[-]
Posts: 668 Feb 22 12 4:25 AM Reply Quote More My Recent Posts	MattReloaded wrote: HK wrote: Here's my take on a low-cost, STOBAR CVL. My starting point is Cavour, but with some significant cost reduction. Air group capacity would be about 16 Rafale M (6 on deck, 10 in hangar) or 20 Gripen NG, plus a few AEW and SAR helos. after all? In this article from Mer et Marine, they seem to suggest that the CDG airgroup won't be more than 30 aircraft in total, i.e. 24 x Rafale, 2 x Hawkeye and 4 x helos. In the same vein, according to Brown's Rebuilding The Royal Navy (page 198), one of the early studies carried out for CVF showed a 39kt CATOBAR carrier with an airgroup comprising 20 x F/A-18, 3 x S-3A and 3 x Merlins. Can a 30kt STOBAR CVL reasonably be expected to be able to carry as much as 16 x Rafale, plus a few AEW and SAR helos ? CdG's max airgroup is closer to 30-32 fixed wing, at least if you stick to USN density standards. (I've spent a good deal of time looking at CdG's deck layout and hangar dimensions). Such a high density setup would work best if you always have some aircraft in the air, i.e. in a high threat environment. However, that number doesn't make sense for sustained cyclical A2G operations (as in Libya)... too much re-spotting. So 26 fixed wing is most likely just a compromise, to suit typical peacetime or coalition operations. As for Cavour, I've shown how she could carry 6 fixed wing quite easily on deck in a STOBAR configuration. 10 more below also seems quite feasible, especially if you clear out some more hangar space by eliminating troop accommodation.
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SpazSinbad		#62	[-]
Posts: 874 Feb 22 12 4:31 AM Reply Quote More My Recent Posts	Every time I see the video clip with this (poor quality still frame as shown) I am gasping at the poor landing. We don't know any details - what the LSO may have been screaming on the radio :-) or whatever else but it sure is a classic 'taxi one'. I could make the clip available on Utube at some point. When it is there I'll post that info here. However the long version is quite entertaining (once removed). :-) Hah, the 'streak marks' in the aft lift can be seen also in the screenshot. I guess the lift was heavily reinforced. A long greyscale film of these and other events of note can be seen at the 'bengello' Utube site: A4G Skyhawk on HMAS Melbourne Deck Ops early 1970s http://www.youtube.com/watch?v=Vy0vWedmc_4&feature=plcp&context=C39a5a6bUDOEgsToPDskJmZA2enoqnczuqu5qanp8X Smoke from main wheels shows touchdown before no.1 wire. Shudder.... Click Pic: [https://skydrive.live.com/]?cid=cbcd63d6340707e6&sa=822839791 & [http://www.]youtube.com/user/bengello/videos Last Edited By: SpazSinbad Feb 22 12 4:37 AM. Edited 1 times.
NewGolconda		#63	[-]
Posts: 7374 Feb 22 12 5:44 AM Multi-Board Moderator Reply Quote More My Recent Posts	"My gut tells me that EMALS/EMCAT would be very expensive. I'd wager that you could pay for another 5,000-10,000t worth of STOBAR carrier for the same price... and between a 40,000t STOBAR and a 30,000t CATOBAR carrier I would pick the former." You are going to need to buy 24 Rafael to get a deployable airgroup of 16 or so. What total ownership cost do you put on 24 Rafael? What price the extra 10Kton and EMCAT together? Your Text Signature ...
MattReloaded		#64	[-]
Posts: 3263 Feb 22 12 5:53 AM Reply Quote More My Recent Posts	HK wrote: - Replace the four LM2500 22MW gas turbines one-for-one with four Wartsila 16V38 11.6MW diesels, with waterline exhausts. Top speed drops to ~24kts sustained deep & dirty, and ~26kts for trials. The diesels should fit in the same machinery room space, though they do add ~300t of weight deep in the hull (which might actually be positive for stability). On the plus side, the diesels also guzzle ~25% less, which allows you to store up to 40% more aviation fuel. As for the waterline exhausts, the rationale is that they eliminate a whole lot of trunking and allow for a much smaller island. Hopefully the fumes won't get into the hangar! One more question : I find the idea of using waterline exhausts quite attractive, but I'm wondering whether such exhausts are likely to create hot air turbulences which might complicate flight deck ops, especially landing ? Would some kind of water-cooling system be required so as to bring down the temperature of exhaust gases ?
HK		#65	[-]
Posts: 668 Feb 22 12 7:13 AM Reply Quote More My Recent Posts	Watercooling would help of course, and has been used on frigates so hopefully could be scaled up for a CVL with 4x11MW diesels. That said, I'm not even sure that the exhaust gases would be an issue. Remember, a corollary of diesels' high thermal efficiency is that there are fewer exhaust gases to deal with. In this case, 45MWs worth of diesels equals 84 kg/s of 390 degree celcius gases (from Wartsila's spec sheet). This is about as much as a lone LM2500+ turbine running at 30MWs... and the GT's exhaust gases are 130 degrees hotter! Finally, the waterline exhausts would be spread out, being split between port & starboard... might be enough to make it a non-issue.
MattReloaded		#66	[-]
Posts: 3263 Feb 22 12 3:32 PM Reply Quote More My Recent Posts	HK wrote: My gut tells me that EMALS/EMCAT would be very expensive. I'd wager that you could pay for another 5,000-10,000t worth of STOBAR carrier for the same price... and between a 40,000t STOBAR and a 30,000t CATOBAR carrier I would pick the former. With UK opting for EMALS, EMCAT is most likely dead (though Converteam might still persevere with EMKIT). Back in July 2010, a fixed-cost contract of $676 million was signed for EMALS (4 units) and AAG (1 unit) to equip the first Ford-class carrier.
MattReloaded		#67	[-]
Posts: 3263 Feb 22 12 4:47 PM Reply Quote More My Recent Posts	HK wrote: - Replace the four LM2500 22MW gas turbines one-for-one with four Wartsila 16V38 11.6MW diesels, with waterline exhausts. Top speed drops to ~24kts sustained deep & dirty, and ~26kts for trials. The diesels should fit in the same machinery room space, though they do add ~300t of weight deep in the hull (which might actually be positive for stability). On the plus side, the diesels also guzzle ~25% less, which allows you to store up to 40% more aviation fuel. I'd go for IFEP, with 8 x 16V32 diesel gensets @ 8,900 kWe each and 2 x electric motors @ 30 MW each. Sustained speed would be about 27+ knots deep & dirty, and 29+ knots for trials. 1) Space and weight The 16V32 genset is fairly compact (L x W x H = 11,175mm x 3,080mm x 4,280mm). Lengthwise, it would in fact be slightly more compact that the CODAD arrangement proposed with the 16V38 diesel engines once the gearbox is taken into account (16V38 length = 8,900mm, TCH380 gearbox length = 3,680mm). As far as weight is concerned, each 16v32 genset is about 120 tonnes, i.e. 960 tonnes for 8 gensets. The electric motors would be somewhere between 100 and 150 tonnes each (lower figure is for PMM, higher figure for AIM), i.e. 200 to 300 tonnes in total. The machinery weight for the Clemenceaus was somewhere around 2,000 tonnes. Compared with the Clemenceaus, the diesel-electric propulsion would cut the fuel consumption by about 50%, meaning fuel bunkerage could be reduced from 3,700 tonnes to 2,500 tonnes. 2) Cost Based on the numbers available for the Type 45 and the CVF (see here, here and here), IFEP costs could be as follows : Diesel engines : $40 million (8 engines @ $5 million each) Alternators & motors : $100 million Power Control & monitoring : $30 million i.e. about $170 million in total. The CODAD arrangement proposed by HK would probably cost around $50 million ($24 million for the 16V38 diesel engines, $16 million for the reduction gears and $10 million for the diesel gensets). Edit : costs adjusted for the diesel engines and reduction gears. Last Edited By: MattReloaded Feb 23 12 3:37 AM. Edited 1 times.
IcelofAngeln		#68	[-]
Posts: 5956 Feb 22 12 5:06 PM Reply Quote More My Recent Posts	""My gut tells me that EMALS/EMCAT would be very expensive. I'd wager that you could pay for another 5,000-10,000t worth of STOBAR carrier for the same price" But against that set life-cycle maintenance costs, which supposedly for EMALS are much, much lower than steam.
MattReloaded		#69	[-]
Posts: 3263 Feb 22 12 6:08 PM Reply Quote More My Recent Posts	HK wrote: - Eliminate the expensive long-range search radar, sonar and local air defense systems (rely on escorts for this). In the absence of a decent AEW solution, I would probably keep the long-range air search radar. IIRC, the RAN-40L costs something like $20-25 million, which remains quite reasonable. Together with IFEP, the 30kt STOBAR I have in mind would therefore cost something like $125 million more than yours, i.e. 10-15% cost premium. Should it one day become available / viable, I'd also go for the single-engined Tejas Navy Mk2 rather than a twin-engined aircraft like Rafale. Life-cycle costs should be much lower, and my feeling is that a single-engined aircraft is a better fit for a 30kt STOBAR for a variety of reasons.
MattReloaded		#70	[-]
Posts: 3263 Feb 22 12 7:09 PM Reply Quote More My Recent Posts	NewGolconda wrote: The 24 Superhornet for the RAAF are going to cost roughly US 5 billion, once you include ten years spares and training support. That’s an operational force around the mid teens - which is in the ballpark of a CVL air group. The acquisition costs of an economy CVL - a stretched ski jump, arrested landing Juan Carlos or something, around 30-35,000 tons - are going to be in the US 1.5-2.5 billion range, unless you are operating with unusual costs structures with third world labour rates. The higher figure is probably more comparable to the "10 year" super hornet price tag, with spares and training. If you want some escorts for the carrier group - let’s say 3-4 minimalist F-100 AWD ships are going to be 2 billion as a minimum - probably more like 3-4 billion on our "10 year" basis. We are going to need at least at least a dozen modern ASW helicopters for carrier and escorts - hard to get by with less than 2 billion here. We could park up all of the other associated costs, intermediate trainers, a fleet train to make the task force long term deployable, shore based infrastructure. So the “10 year” acquisition plus initial support costs for a CVL based task force are something like. Airgroup – 40% CVL – 20% Escorts – 24% ASW choppers – 16% Total – US 12.5 billion 100% On this basis – a larger ship with an EM catapult might cost you what, another billion? <10% of the total task force cost? And what do you gain in terms of air group effectiveness over a small ship with a 9deg ski jump? 25% - 40%? The bigger ship is going to be able to recover aircraft over a wider range of weather conditions, and store more fuel and munitions. In fact, you might be tempted to increase the size of the ship again to maximise those factors. What’s that – another billion, but only another 10% in terms of the cost of the task force. Of course, we can now carry two dozen Hornet sized aircraft or more, if we can afford it. All of a sudden we are in CVF territory. If you are using full priced, modern first world jets in the airgroup, the airgroup costs swamp the carrier costs – have from as early as 1960 from what I have colated. Which means spending more money on the carrier to optimise the performance of the airgroup is exactly what you are going to do – which then goes on to explain US, British, and even French (in the last decade) carrier decisions since the mid 50’s, and why we so few conventional CVL’s entering service. My take : 1 STOBAR CVL @ 30 kt : $1.5 billion 30 Tejas Naval Mk2 @ $50 million each : $1.5 billion (CVL typical airgroup is 20 aircraft) 20 ASW helos @ $50 million each : $1.0 billion (CVL typical airgroup is 10 helos, plus 1 helo per DDG) 3 DDGs @ $700 million each : $2.0 billion That's a total of $6 billion for acquisition only. Going CATOBAR with EM stuff probably alters the numbers that way : 1 CATOBAR CV @ 45 kt : $3.0 billion 36 Rafale @ $100 million each : $3.5 billion (typical airgroup is 24 aircraft) 3 AEW aircraft (E-2C) @ $250 million each : $0.75 billion (typical airgroup is 2 AEWs) 15 ASW helos @ $50 million each : $0.75 billion (typical airgroup is 6 helos, plus 1 helo per DDG) 4 DDGs @ $700 million each : $3.0 billion That's a total of $11 billion for acquisition only.
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MattReloaded		#71	[-]
Posts: 3263 Feb 22 12 8:27 PM Reply Quote More My Recent Posts	Below are some rough estimates I came up with for the 30kt STOBAR I have in mind : 1) Main particulars : LWL = 240 meters LOA = 260 meters BWL = 32.5 meters BOA = 50 meters Draft @ max displacement = 7.5 meters Freeboard @ max displacement = 14.5 meters Block coefficient = 0.51 Full load displacement = 30,000 tonnes 2) Aviation installations Hangar dimensions = 120m x 24m x 6m (L x W x H) Angled deck = 180m x 18m (L x W) with Svetlana-2 arresting gear (90m runout) Flight deck area = 9,000 sq. meters Axial TO run = 195m x 18m with 14°3 ski-jump Elevators = 17m x 13m (2 centerline elevators, offset to starboard) 3) Typical airgroup 20 x Tejas Mk2 aircraft (or equivalent) 6 x ASW helos (Merlin ASW ?) 3 x AEW helos (Merlin AEW or BA609 AEW ?) 4) IFEP Propulsion 8 x Wartsila 16V32 gensets @ 8,900 kWe each 2 x Electric motors @ 30 MW each max. speed = 29 knots max. sustained speed = 27 knots cruise speed = 18 knots range = 10,000 NM @ 18 knots 5) Displacement breakdown Lightship = 23,000 tonnes Bunkerage = 2,700 tonnes AVGAS = 2,600 tonnes (about 3,200 m3) Ammos = 500 tonnes Food = 200 tonnes Water = 500 tonnes Aircraft = 350 tonnes Complement = 150 tonnes Last Edited By: MattReloaded Apr 20 12 12:02 PM. Edited 2 times.
hrfcarl	Nuclear Power worthwhile?	#72	[-]
Posts: 635 Feb 22 12 9:03 PM Reply Quote More My Recent Posts	For lower rank counties, obtaining nuclear reactors is an issue, so this question is for those countries in the nuclear club: Is nuclear power too expensive (personnel & materials) and/or space consuming vs gain in fuel storage and endurance for a smaller class of carrier? Also: By need it seems a carrier will be the largest warship in a fleet, so not worth the extra equipment/tonnage/size and associated cost to make carriers of a smaller fleet the C&C/flag ships? Defensive weapons mounted should be limited, but have the ability to control the weapons on its escorts - AEGIS or equiv on carrier with escorts holding the weapons, of course 1 other escort should have this C&C system as back up, so then rest of the escorts could be FFGs. Last Edited By: hrfcarl Feb 22 12 9:09 PM. Edited 1 times.
HK		#73	[-]
Posts: 668 Feb 22 12 10:02 PM Reply Quote More My Recent Posts	MattReloaded wrote: I'd go for IFEP, with 8 x 16V32 diesel gensets @ 8,900 kWe each and 2 x electric motors @ 30 MW each. Sustained speed would be about 27+ knots deep & dirty, and 29+ knots for trials. 1) Space and weight The 16V32 genset is fairly compact (L x W x H = 11,175mm x 3,080mm x 4,280mm). Lengthwise, it would in fact be slightly more compact that the CODAD arrangement proposed with the 16V38 diesel engines once the gearbox is taken into account (16V38 length = 8,900mm, TCH380 gearbox length = 3,680mm). As far as weight is concerned, each 16v32 genset is about 120 tonnes, i.e. 960 tonnes for 8 gensets. The electric motors would be somewhere between 100 and 150 tonnes each (lower figure is for PMM, higher figure for AIM), i.e. 200 to 300 tonnes in total. The machinery weight for the Clemenceaus was somewhere around 2,000 tonnes. Compared with the Clemenceaus, the diesel-electric propulsion would cut the fuel consumption by about 50%, meaning fuel bunkerage could be reduced from 3,700 tonnes to 2,500 tonnes. 2) Cost Based on the numbers available for the Type 45 and the CVF (see here, here and here), IFEP costs could be as follows : Diesel engines : $70 million (8 engines @ $9 million each) Alternators & motors : $100 million Power Control & monitoring : $30 million i.e. about $200 million in total. The CODAD arrangement proposed by HK would probably cost around $90 million ($45 million for the 16V38 diesel engines, $30 million for the reduction gears and $15 million for the diesel gensets). My reaction: IFEP is a non-trivial exercise (in terms of cost/volume weight increase), and should only be considered if there is a very specific operational need for it. I just don't see it for a CVL... Let me summarize the downsides: - You're replacing four compact GTs ( LM2500, 8.2m x 2.7m x 3m, 22 tons) or four slightly larger diesels (16V38, 8.9x 3m x 4.7m, 110 tons) with eight very large gensets (16V32, 11.2 x 4.3m x 3.3m, 140 tons). Add in the 80t weight differential between a mechanical gearbox and electrical motor... now that's 800 tons more weight and 125% more volume than the CODAD solution... which itself is 300 tons more weight and 200% more volume than the baseline COGAG solution on Cavour. So you're looking at a much larger hull... 35,000t? - Fuel costs: smaller diesels and electrical losses will add 10-12% to your fuel consumption at cruising & high speeds - Capital cost: I get about a 3x cost difference between 45MW CODAD and 80MW IFEP ($40 vs. $120 million). Your estimates seem high on both ends. ... all in all, your suggestion starts moving you down a very slippery slope... towards a fleet carrier. People will say, "oh why don't we add a 3D radar", then "we've got all this generating capacity...let's add EMALS", then "let's make it a medium carrier... 45,000t should do it", then "we've now got a $2 billion carrier, we can't leave it defenseless"... at the end of that vicious cycle you end up with CVF.
HK		#74	[-]
Posts: 668 Feb 22 12 10:14 PM Reply Quote More My Recent Posts	MattReloaded wrote: Below are some rough estimates I came up with for the 30kt STOBAR I have in mind : 1) Main particulars : Draft @ max displacement = 7.5 meters 3) Typical airgroup 20 x Tejas Mk2 aircraft (or equivalent) 6 x ASW helos (Merlin ASW ?) 3 x AEW helos (Merlin AEW or BA609 AEW ?) 5) Displacement breakdown Lightship = 23,000 tonnes Airgroup is a very tight fit... those Merlins take up a lot of space. The hull you're suggesting is bigger than Clemenceau... the draft is way too low for good stability. You just had to add 1,000t of machinery, double the machinery space volume, add an angled deck... and light ship only increases by 1,900t vs Cavour? ... not going to happen. See my previous post... realistically you're looking at a 35,000t carrier.
PK		#75	[-]
Posts: 1089 Feb 22 12 10:50 PM Reply Quote More My Recent Posts	hrfcarl wrote: For lower rank counties, obtaining nuclear reactors is an issue, so this question is for those countries in the nuclear club: Is nuclear power too expensive (personnel & materials) and/or space consuming vs gain in fuel storage and endurance for a smaller class of carrier? IIRC, just the shielding for one K15 reactor of CdeG is 800 tons and one complete propulsion train more than 2.000 tons. Plus the steam part needs a lot of volume and requires a large and highly skilled crew. The larger range IMO is practically unimportant, as your escorts need fuel as well as your planes. Last Edited By: PK Feb 22 12 10:53 PM. Edited 1 times.
PK	Back to the start?	#76	[-]
Posts: 1089 Feb 23 12 1:19 AM Reply Quote More My Recent Posts	(Sorry, I was some days off and just cross-read this thread. So maybe I have missed the key posts. ) When discussing a Light Aircraft Carrier, my starting point would be the mission. Example: If the task was Anti-Piracy, I would first look at a long-range intelligence platform. No high-end radar to discover incoming supersonic sea skimmers and no flying control center - in short, no Hawkeye. Maybe some rugged MALE drone (Predator, IAI Heron or the like) could be adapted with folding wings and a tailhook. For the action, a light jet would be adequate for a light carrier. Whether Gripen NG or Tejas-N or something else doesn't matter to me, but two tons of ordnance at 400 miles looks like a reasonable capability. Supersonic would be no key requirement for me, buddy refuelling would be more important. Some long-range helos would complete the setup; say S-92 or NH90 (Merlin might be too big a beast..) Maybe 4 drones, 12 jets and 4 helos as standard, an additional 12 jets as maximum. Standard scheme would be one drone in the air and two jets ready to launch. In case of need, another 4 jets should be launched a short notice and 2 jets would be equipped for buddy-buddy refuelling. If that's a plausible modus operandi, it could then be checked whether the gadgets can take off with own power or if they need assistance. SO -what would be the job for a CVL, and what tools would be put onto the carrier to fulfill it?
Zen9		#77	[-]
Posts: 5919 Feb 23 12 2:12 AM Reply Quote More My Recent Posts	LWL = 240 meters LOA = 260 meters BWL = 32.5 meters BOA = 50 meters If the LWL is 240m, then 75% is 180m + 20m (radius from the locus) is 200m + bow overhang of 10m gives us 210m However we need to take off the length of the angled deck from the bow say at 67m leaving some 143m. Good news is the angled deck angle adds some more to that. But thats the rough estimate you've got to work with.
MattReloaded		#78	[-]
Posts: 3263 Feb 23 12 3:18 AM Reply Quote More My Recent Posts	HK wrote: - You're replacing four compact GTs ( LM2500, 8.2m x 2.7m x 3m, 22 tons) or four slightly larger diesels (16V38, 8.9x 3m x 4.7m, 110 tons) with eight very large gensets (16V32, 11.2 x 4.3m x 3.3m, 140 tons). Add in the 80t weight differential between a mechanical gearbox and electrical motor... now that's 800 tons more weight and 125% more volume than the CODAD solution... which itself is 300 tons more weight and 200% more volume than the baseline COGAG solution on Cavour. So you're looking at a much larger hull... 35,000t? 1) It's really a matter of perspective : your reply is solely focused on the Cavour, and completely leaves aside the comparison with the Clemenceaus. a) I don't have the exact machinery weight for the Clemenceaus, but here are some weight data for similar steam plants : CV-TCBL (Preliminary design, Feb 1975) : 1,986 tons for 134,000 hp (source = Friedman's US CVs) CVV (Design Study, August 1977) : 2,171 tons for 140,000 hp (source = Friedman's US CVs) GW 9A Missile Cruiser (Design Study, November 1956) : 2,258 tons for 110,000 hp (source = Friedman's British Cruisers, WW2 and after) b) Likewise, the numbers for the Tarawas are as follows (source = Friedman's US CVs) : Propulsion : 1,352 tons for 70,000 hp Electrical : 759 tons for 14,000 kW c) I am therefore comfortable with an estimate comprised somewhere between 2,000 and 2,500 tonnes for the Clemenceaus and their 126,000 hp. d) Trial displacement for the Clemenceau was 30,024 tons, with a draft of 7.85 meters amidships. e) Based on the Clemenceaus, I feel comfortable with the numbers I came up with, i.e. FLD = 30,000 tons, draft @ FLD = 7.5 meters amidships and the IFEP I described earlier. f) IOW, I am not looking at a 35kt hull as you suggest. 2) There are some inaccuracies in your weight analysis based on your Cavour perspective : a) you've completely left aside the Gensets, which, by definition, are included in the weights I posted for the IFEP. For the real Cavour, there are 6 x Wartsila 12V200 CW.@ 27 tonnes each, plus another 2 generators / alternators of 2,200 kW each, representing a total weight of about 200 tonnes. For your Cavour mod, I am assuming you'd use 4 x Wartsila 12V200 CW @ 27 tons each, representing a total weight of about 110 tonnes. b) you're underestimating the weight of the gearboxes : For the real Cavour, each gearbox is about 76 tonnes, which means a weight difference comprised between 25 and 75 tonnes vs the electric motor. For your Cavour mod, each TCH380 gearbox is about 70 tonnes, which means a weight difference comprised between 30 and 80 tonnes vs the electric motor. c) The Wartsila 16V32 is 121 tonnes, and not 140 tonnes as you wrote. d) Your Cavour mod therefore comes with an aggregate weight of 690 tonnes (4 x 16V38 @ 110 tonnes each = 440 tonnes, plus 2 x TCH380 @ 70 tonnes each = 140 tonnes, plus 4 x 12V200 @ 27 tons each = 110 tonnes). The IFEP is somewhere between 1160 tonnes and 1260 tonnes, which means somewhere between 470 and 570 tonnes more than your Cavour mod, and not 800 tons as you stated earlier. Even using your Cavour perspective, I don't quite see how this weight difference of about 500 tonnes would translate into a 5,000 tonnes in terms of FLD. 3) As far as volume is concerned : a) Using the plans of the Clemenceaus, I believe the IFEP would fit inside the same footprint as the existing steam plant (length = 62 meters between frame 81 and frame 143, width = 18-20 meters). b) Based on this somewhat basic drawing of the existing Cavour, I also have a feeling that the 16V32 gensets would easily fit inside the engine rooms : * each pair of LM2500s with gearbox is over 14 meters long and 6 meters wide, whereas each 12V200 genset is about 7 meters long and 2 meters wide. * each 16V32 genset is 11.175 meters long and 3.060 meters wide. There also seems to be adequate room for a couple of electric motors : the 36.5 MW PMM by DRS is 5.1m x 5.4m x 5.3m, meaning a scaled-down 30 MW PMM would be about 5m x 5m x 5m.
NewGolconda		#79	[-]
Posts: 7374 Feb 23 12 3:25 AM Multi-Board Moderator Reply Quote More My Recent Posts	It is my working hypothisis based on bits and pieces picked up here and there, that ship design today can produce significantly more useable internal volume and wieght reserves on less displacement than was the case in the 50's due to the use of better materiels (higher grades of steel) and better engineering practices (finite element analysis?). Thats aside from issues relating to new propulsion types and improved power to wieght ratios. One of the reasons why modern large vessels, like the Cavours, or the Juan Calros's - or for that matter modern car carriers, container ships - even cruise ships look so top heavy, short fat and bulky to eyes accostomed to the lower, more elegant lines of earlier generation vessels. Your Text Signature ...
bager1968		#80	[-]
Posts: 7595 Feb 23 12 3:27 AM Reply Quote More My Recent Posts	Also the use of active stabilization devices allows building ships with less "natural" stability than before. Who'd have thought 30 years ago Hermes would still be in active service when Invincible was at the breakers yard?
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What future for the Light Aircraft Carrier?