Tuesday 3 March 2009

Dream Corvette

In responce to Mike Burelson's recent posts, I have decided to generate some specifications for a general purpose corvette, to service the Royal Navies requirements, what do you think?

Displacement: 1500-2000tons

Range:10000nm at 18kts

Speed: 29kts

Crew: 60

Armament;


  • 1* 57-mm Mk 110 Mod 0 Naval Gun System (mounted forward)
  • 2* two 35 mm Millennium CIWS guns mounted towards rear on either sides of hangar - these have been chosen allong with MK110 (which can be used in the CIWS role), now the reason I have put two in is due the desire for these ships to be capable of surviving a heavy missile attack and as added defence against swarms of motor boats - something which could present in the modern littoral enviroment; however I must admit it would be cheaper to mount 1 centerline on the hangar - this combined with the MK110 would be purfectly servicable if not as powerful as I would personally prefer
  • 24/32 cell MK41/53 VLS – mounted between hangar & bridge - these can be loaded with Tomahawks, Standard Missiles (2, 3, & 6) or Aster Missiles (15 & 30) and Asroc - which if mounted then torpedoes might not be fitted to save costs
  • 2*two stanflex containers, initially to be loaded with 16 harpoon SSM – mounted forward of bridge in ‘B’ position
  • 2* TRIPLE torpedo launchers – to flank the vessel; as back up if the others fail

Sensors:

  • Air Search: The same BAE Systems Insyte / Thales S1850M radar operating at D band as is installed in the T45 AAD -this I would like too install because I think a corvette given a general purpose role will need a good air search radar, although this might make it too top heavy
  • Air/Surface Search: SMART-S mk2 is my first choice as this will also provide a measure of Air Search as is to be installed on the Project Khareef
  • Command Control System: TACTICOS - because it is good, of the shelf so not expensive, and has been proven to be a system of choice for corvettes
  • ESM: Vigile 400 ESM, after reading about it in the article on Project Khareef, I looked it up and felt it was the right choice
  • Sonar: Type 2050 medium-range bow-mounted active / passive search and attack sonar the same as is in the Type 23 F
  • Communications: Shaman communications-band electronic support measures (CESM) system
  • Fire control: Thales Naval Nederland - as is fitted on the German K130 corvettes

Decoys

  • Chaff launchers/flares
  • DLH active naval offboard decoy system as has been fitted in Type 45 AAD

Aircraft

  • 1*Super Lynx & 1* UAV, or
  • 3* UAVs

Boats

Propulsion

  • Gas driven waterjet system. With instead of a conventional funnel, a waterline engines exhaust system will be used. This configuration will reduce the vessels thermal signature as well as benefiting operations by allow a 360° vision capability from the bridge.
  • From Sven; a combined Stirling-electric engine with a propeller (not as efficient as diesel, but very silent) and a sprint gas turbine with forward/center waterjet.
  • Hydrogen will be considered as an option

Design

  • All edges are to be sloped 7˚ as in duke class
  • coated in radar absorbing paint
  • however will not be designed as a ‘stealth’ ship

Estimated cost; £55-65million - a bargin!

So what do you think?

*****

This is the third draft taking into account all that has been discussed

*****

That is a good corvette, but the http://www.naval-technology.com/projects/visby/ is better in its range and capabilities, and I think they can be bettered still with the adition of decent VLS, and built of a slightly larger size than some which are built now - although although the Sigma class is more of the size I am interested in employing; Project Khareef http://www.naval-technology.com/features/feature1476/ is a prospectively good example of this, if the next three that are planned to have Type 41 or 53 vls installed are built.

******

Terry

in reply to your post;

My personal observation is that a netted architecture is invaluable when working with other ships, aircraft or sensors. It is a true force multiplier allowing one unit to share time/space/position data of the good and bad guys with others. Assume Link-16 at a minimum and maybe something more robust at the higher end.

this was considered standard, but there are a current number of specialist ones being developed for various corvette classes in production; I did not want to make a selection to soon - although the Royal Navy does have its own standard one, so a version of this might be installed


Other thoughts:

1. 60 is too small a crew. Try a work force analysis with all of the funtionality that you envision and these guys will never sleep.

http://www.naval-technology.com/projects/visby/ - I would point too the swedish visby class corvette, whose compliment is 43, but crew is only 20 - the other 23 are mission applicable


2. Get rid of the helo.

I agree with this, but I included it as a considered option because the reason the RN keeps giving for building frigates instead is that they need the 'force multiplication value' which comes from helicopter operation; I think personally if you need the helicopter send a bigger escort!


3. I like the USV, but there continue to be C2 issues with these guys: seemingly more complicated than a UAV to control.

have you seen the Rafael USV http://en.wikipedia.org/wiki/Protector_USV? there are others like the Seastar http://www.aeronautics-sys.com/?CategoryID=264&ArticleID=207 ; these systems have been itegrated and up and working for a while, to my mind they are more useful than a helicopter for a corvette; as any vessel working in the littoral will need capabilities they will provide - the Protector is my favourite, as it is proven, and is very much off the shelf.

hope this answers your questions

Alex

*****

Sven, I will attempt to answer your questions - there is no such thing as a pessimistic comment, I feel if you can not defend your ideas against all angles, they are obviously not as well thought out as they should be.

crew - likely much too small
I can see your point by, but as the swedish visby has a crew of 43, and the K130 class of the German navy (http://www.naval-technology.com/projects/k130corvette/) is only 50, so I feel I actually gave it more than will be needed

Range - this is unnecessarily long. This is not meant to be a cruiser, after all.

I chose the range because whilst it might seem unnecessarily long, it will provide with a very wide range of independent unsupported action; purfect for Britains wide flung commitments, as well constant operations in the south atlantic.

guns - lacking a manually or remote-controlled autocannon or machine gun mount for very close encounters

The 57-mm Mk 110 Mod 0 Naval Gun System (mounted forward) combined with the two 35 mm Millennium CIWS should provide more than enough protection, however if you do go for only on CIWS, then the fitting of a couple of Rafael Typhoon's should make up for those deficiencies which would then be realised

SSM - twice as many as the internationally agreed standard. You might consider the more modern and countermeasure-resistant NSM

That is possible, but the 16 Harpoons is the same Absalon Class, most importantly with their land attack capability incorporated into the new version of Harpoon - added to all this is the fact that as a tried and tested system it will not be expensive to attach. remember the whole point of this corvette is that is cheap and sustainable escort for providing the bulk of future fleets as well as fulfilling water policing/flagshowing and guard ship roles. This is another reason for the heavy SSM capability, as in support of what you pointed out next.

VLS - the long strike version, a questionable choice for a corvette

VLS - was chosen because of its capability in providing the wide range of options; a limited long range missile strike from a corvette might be all you can put in area; but it might just be enough and is always better than nothing; besides for me the combination of

triple torpedo launcher - (lightweight 324mm?) saving that (see your VLS remarks) won't save any significant sum. The launcher is cheap and used examples are in arsenals. You need the lightweight torpedoes anyway for the helicopter (that's imo the primary reason why these launchers are so common).

well as I pointed out these vessells might not be running a helicopter; and if they are then it may be fitted; I have nothing against them - I would be using the lightweight torpedoes.

Sensors in general - FFG/DDG equipment in a small corvette that's also stuffed with weapons; I feel that this isn't possible (also see: SAMs).

that is a judgement call, I feel modern corvettes are getting more and more heavily armed, as they take on more roles which during the cold war were the purview of larger escorts; if you are going to fit these weapons to give it the advantages it needs, then you have to fit the sensors to match the weapons.

Sonar - outdated afaik. An modern active low frequency VDS like LFTAS would be a much better idea vs. SSK.

that as maybe true; but again instead of going for expensive new equipment, which is under development I decided to go for tried and tested systems which we know work, and we know how to make them operate to their best ability.

(LL)TV, IIR and LRF sensors - missing, but essential for object identification and passive surveillance

again I thought these would be considered standard; I know they are part of the Royal Navy's standard build so I just felt that is what would be put in, whatever anyone else said.

Communications suite - missing

not missing the same as above; Royal Navy have a standard system; however it will be affected by the command system chosen, which perhaps you will have a better understanding of which of them is best - I currently can only the see the SAAB system on the Visby; which is based on the RN's efficient ship project as a system with any lead over the competition but this is only marginal.

ESM - is Vigile 400 only ESM? Modern ships of that size need ECM, too.

yes, but what would you recomend, the Vigile is designed for corvettes - the German K130 only has the EADS SPS-N 5000 radar ESM.

SAM - that's the choice for an AAW DDG or FFG, not for a corvette. Mica VL, BAMSE and Barak SAMs are more suitable, or ESSM if an illumination radar capability is available

I knew people were going to say this; and I understand what you are saying; however I still believe that if they are going to operate on their own then a corvette deserves, no requires, the same capability of intercept as its larger counterparts.

Subroc - this is a sub vs sub weapon, I think you meant Asroc

sorry sometimes I do mix up the two; I have changed it

Boats - missing. Dinghy could be used as decoy especially with simple broadband ECM against home-on-jam missile modes, minimum: installation of decoy launcher and remote control/autopilot

for boat read 'launches' - sorry the Royal Navy call subs 'boats' and ships boats 'Launches'

Propulsion - gas turbines aren't very efficient & never silent, waterjet isn't as efficient as propeller IIRC. Gas turbines produce a lot of exhaust gasses, pressing all that into the water is loud and means loss of efficiency (not advisable as permanent measure).I would rather choose a classic CODOG installation or a combined Stirling-electric engine with a propeller (not as efficient as diesel, but very silent) and a sprint gas turbine with forward/center waterjet.

I like this the later one, hence it has been added above for consideration

Hydrogen - no support infrastructure in harbors, no support capability in support ships, requires huge volume and lH2 limits mission endurance due to vaporization or requires a re-liquefaction system

An interesting analysis, on the topic of Hydrogen, I would point out that before the Queen Elizabeth Class Super-Dreadnoughts there was no infrastructure for oil powered ships either; if this is the new propulsion you need then you have too build it; oil/gas fossil fuels in general are getting more expensive and its supply is coming under more threat as it is found in places which are less and less politicaly stable - Hydrogen is all around us; a nuclear powered carrier could generate the Hydrogen for its battlegroup itself; now that would be really good infrastructure

roll stabilization system - missing
harbor maneuvering system - missing (a simple retractable fin in the path of a forward/center waterjet would do the job)
external fire hose / fire fighting system / water projector - missing, but relevant for OPV use (I don't know the correct English word)

All of the above are fitted as standard; although my personal choice for roll stabilitzation system would be the RNLI's new system (I think its called 'glide' but not sure)

cost - unrealistic unless you build hundreds of these in PRC

Again I can see your point, but disagree, as if you do build using conventional off the shelf technology, and you use a convetional build system it is certainly possible; most importantly if I were in charge I would want about 48 of these in service, so that would make it possible for such a Per Unit Cost.

overall - add 100 crew, another Lynx and 4,000 tons and you've got a GP DDG.You've stuffed too much into it for a corvette and neglected ASW (especially sound stealth) and unspectacular components.

I have put in what you term unspectacular; what I call, cost effective tried and tested equipment - its the Sherman(upgunned) rather than the King Tiger. Whilst it is heavily armed, to be fair you haven't seen my destroyer specks yet. Added to this, I think that the sound stealth would suprise you - but that does not matter as much your remark about it having to much arnament for a corvette; this suprised me as I think the more capable a warship is the better armed warship, and a corvette in the littoral enviroment needs to be able to defend the Amphibious ships as well as defend itself.

@Mr. Johnson: Helicopters are extremely versatile and useful. UAVs alone cannot cover the mission spectrum yet. Corvettes are not really a good choice in strong battlegroups and operate rather outside of friendly helicopter support.

I disagree I feel a combination of destroyers and corvettes is a far better combination of escorts for a battlegroup - especially in littoral regions, than frigates; which are not as powerful as destroyers, and too expensive to build in the required numbers.

*******

B-smitty

There's no way you'll fit all of this stuff on a 1500-2000 ton corvette. The equipment you've spec'd might fit on a 5000 ton frigate.

this is a range of equipment to fit in it, and I think it will, for starters without the helicopter but carrying smaller UAVs; I am also keen on making the vessel as simple as possible in design so that in can afford to insert these...oh and a corvette is any vessel up to 2800tons....I think with a little bit of skill and luck it could be fitted in

Look at similarly-sized corvettes such as the German K130 for a reasonable configuration.

Its a very interesting configuration, and I have gone for similar, I have just increased the load a little, and replaced its RAM system with a proper VLS.

The K130s cost around $300 million (USD) each, IIRC, so I think your estimated price is low.

I might well have to accept this, but I also believe that if you use conventional proven technology, and keep the design simple and build enough of them; plus limit the builders to an acceptable degree of profit, then is no reason why unit price could not be £60-80million; as I have said before I would plan on building a lot of these vessels thus reducing the price considerably; and due to the use of existing tech, would keep development costs down to a minimum.

yours sincerly

Alex

****

B Smitty

If you drop the VLS, the rest might fit. A warship can expect to carry 5-10% of it's light ship displacement in payload. If your corvette's light ship is 2000 tons, then that means 100 to 200 tons of payload. A loaded, 32 cell Mk41 VLS weighs around 100 tons by itself! (for comparison, a RAM launcher only weighs around 6 tons)

Smitty you are right, it is usually for it to be 5-10% of weight, so if you built the maximum 2800ton corvette, it would be 280tons in weapons at maximum - more than enough for the vls, which is key to providing it with the capability it requires.
Plus a strike length cell is 25 feet long, which will be tough to fit in a small hull, especially 24+ of them.

I know, so it will have to be a little on the long side for a corvette

yours sincerly

Alex

******

B.Smitty

A 2800 ton light ship means over 3000 tons full load. Certainly this is more reasonable for a VLS, though there aren't any ships of this size with 24 or more Mk 41 cells. This is roughly the same size as a Type 21 frigate, btw.

I concur; but the sizes have moved up, and the Type 21 or Type 12 frigates were both very good designs, although the type 12 was posibly the most successful frigate design of its age.


IMHO, a reasonable armament for a future British 2000-2500 ton (full load) "corvette" would look something like this,
- 1 gun (whatever the RN wants in this class)

the BAE MK110 is about the best for this, as I don't think the 4.5in standard issue would be a good choice

- 8-16 Slyver A43 cells with Aster 15 & CAMM quad-packs

why did you pick the Sylver? why? I beg you - its awful, the Type 41 is cheaper, and has a better range of weaponry; also its made by BAE in britain, and I know this is going to sound stupid coming from a British person, but in times of financial crisis I think the government should try and sources these things from within the nation.

As for Aster 15 or CAMM, I prefer a CAMM/Aster 30 combination, as it gives the depth of defence whilst also providing the mass protection of the shorter range camms for dealing with saturation attacks.

The type 41 also has the advantage of packing Tomahawks; a useful force multiplier.

- 8 x Harpoon

a standard arnament, but I feel the Absalon class has shown that a vessel fighting in the littoral needs the extra fire power.

- 1 CIWS (or additional A35 cells for CAMM)

I prefer the option of two, however if one was fitted I would want to fit 2/4 Typhoons instead of the 2 x 30mm guns

- triple torpedo mounts (though one US Admiral said you might as well add a lifeboat launcher rather than torpedo mounts these days because if you're in range to use them, you're about to eat a torpedo)

I agree if its close enough to need them, then its to close, hence I like the ASROC fitted in the Type 41 VLS....it gives far better depth

- 1 Lynx-sized helo pad and hangar
Well I can't argue with this, but I prefer UAVs to manned helicopters as they take up less space, I think at least one for fire spotting is of advantage along with the helicopter...although 3 UAVs are certainly more useful to my mind.

Just MHO.

why no USVs?

yours sincerly

Alex

*******

B. Smitty

I chose Slyver only because the RN chose it for the Type 45. Being American, I certainly think Mk 41 is preferable, but the UK has hitched its horse to the Aster/Slyver wagon. It doesn't make sense to change for this class.

for starters the civil service are making a big deal out of the fact the Type 45s were built with a minimum of naval officers; another is that the Type 41 was turned down (and there is a report I have seen stating this) because it was felt the Sylver fitted better with the then governments political ideas. The Conservatives (the current opposition party, and the ones tiped to win the next election) have said they would change to a Type 41 vls in the the later Type 45 Destroyers, along with the 155mm gun.

B. it is also not unusual for the RN to have a range of different systems across its levels/classes in fact this is incouraged. With the number of submarines in service with the RN shrinking all the time, the corvettes with the Type 41 would also be able to fill the TLAM role nicely with Tomahawks; thus there would only be a minimum loss of capability.

A 3000+ ton ship could carry a small number of Slyver A70 cells, if you really, really want TLAM. Personally, I don't think it's worth the weight and cost for a low-end frigate.

I concur, but I personally feel that frigates are just to big to be made in the numbers requires, and to small to be able to justify that. A corvette/destroyer mix seems a better solution to me for the RN's problems with escort numbers/commitments.

How has Absalon shown that it needs more than 8 x AShMs? Has it fired any? It gets a lot of use out of its helos and boats in CTF 151, but hasn't had to fire a shot of any sort in anger, AFAIK.

No it has not fired a shot in anger, but my point was this with those mountings you can swap and change around; in reaction to the fact that we have not fitted AShMs to our Type 45 Destroyers, you may want to give the other escorts a boost in this area; on the other hand you might want to 4 pairs of exocet launchers (although there is apparently a version of this which can be launched from a Type 41 VLS, in which case I could legitmately say take them off all together, all we need is the VLS and some guns; however as I am not sure of this, I will not say that; although the Tomahawk those definitley have a AShM capability; which would render this with a point); the system can also mount (if put with no obstruction to the sea) two torpedo mounts and two Quads of Harpoon, it is a very goood system.

VL-ASROC is certainly an improvement over triple mounts over the side, but a torpedo-armed helo betters both. Until someone produces a UAV with a dipping sonar that can carry torpedoes (not to mention perform SAR), I'll stick with the manned helo.

I suggest you go on the BAE site, or the German equivalent whose name I can't remember (or sorry have time to research at the moment) but you will find the KC130 mounts three UAVs with dipping sonar, and can carry 1 helo torpedo; okey not brilliant but backed up by VL-ASROC and you could have two or even all three operating; then I would say at least as effective at most ranges as the manned helo.

Alex, I get the impression that you want to build a frigate here. Area air-defense, long-range surface strike and high-end ASW really aren't tasks for a corvette.

well you have to a certain extern rumbled me, I desiging here a mass production capable corvette which can replace the frigates, and cover for the diminishing submarine fleet, as well as be of use in protecting amphibious task groups. Oh and by the by; although our Frigates do have the high-end ASW, they don't have Area air-defence or Long-range surface strike (they just mount Seawolf & Harpoons); I did actually consider Seawolf instead of Aster 15 or CAMM until it was pointed out to me, that Aster was in a lot of trouble till BAE transfered all its SuperSeawolf team to it...and that the Aster missile looks a lot like seawolf; especially the new seeker unit it is fitted with.

yours sincerly

Alex

******

B. Smitty

It doesn't feel like a good idea to have multiple, similar VLS systems in service. You won't maximize your R&D money spent on integration, and will have yet another unique system to support. That being said, if the RN decides to go with Mk41 for future Type 45s, then by all means, use it here too.

Yes it doesn't seem like good money, but it is what has been happening, and looks like it could continue. besides which the RN's R&D money is always overstretched, so whats a little more.

The RN also doesn't use VL-ASROC, so that would be another new system.

A new system which even you have to agree is useful, besides America uses the Type 41 & VL-ASROC, so the RN could always just purchase it as one complete set.

I wouldn't expect a corvette-sized vessel to be a primary TLAM shooter. A ship of this size will likely only have 8 or 16 strike-length cells (and only if you make sacrifices elsewhere), some of which will have to carry ESSM, VL-ASROC or SM-2. So just carrying 2 or 4 TLAMs isn't much help, IMHO. Better to let your big ships carry TLAM in larger numbers.

Size is not the major cost driver in warships. "Steel is cheap and air is free", as they say. The big cost driver is the desire to pack a ship full of expensive combat systems. You can have a larger ship if you exercise restraint and keep the combat systems to the bare minimum. A larger ship has more room for upgrades over its lifetime, handles rough seas and combat damage better, and is generally more comfortable for its crew.

Yes, what you say is true, but a) the big ship will never be subject to such constraint - plus the Treasury would never allow the RN to build a ship which did not utilise every square milimeter of space, b) if you build corvettes you could build enough to allow to put a pair or even more on the operation, so whilst you might have only eight TLAMs loaded per unit, you could mount 32 between them, as well as a very flexible little force, c) whilst the larger units might be available for american ship yards too build, british shipyards have been so run down, that with the Astute program, the Daring program and the Queen Elizabeth II program, we only have yards left which can build heavily armed corvettes. Sorry this is a medium power, whose government has mismanaged industry to such an extent that it has been seriously undermined.

I'm not sure which UAV you mean. The one I've seen mentioned for the K130 is the S-100 Camcopter, which is way too small to carry torpedoes or a dipping sonar. Firescouts may one day carry a dipping sonar, but they are too small to carry current generation torpedoes. They may one day carry the smaller torpedoes under development. Regardless, a manned helo is still more flexible. You can't do this, http://www.aiai.ed.ac.uk/project/cosar-ts/img/uk-sar-3-600x800.jpg with a UAV. At least not yet.

Well no, you can't, but you can do everything else. and the types of UAV I am talking about are like this one http://www.victory-systems-uav.com/uavp-vtoluav.html becoming more and more common; and BAE has a nice line of them coming along.

yours sincerly

Alex

*****

if this was a dream corvette, and it was only allowed 1 CIWS, I think I would be sorely tempted by this system; http://www.youtube.com/watch?v=guVLqfiCfO4 - just watch, and think does this http://www.youtube.com/watch?v=S2R4XAz193U really compare with it?

Alex

********

Kobus, thankyou for that, I wish you could be made Sir Kobus for your actions, but you will have to make do with just my humble thanks, what a great video, and a perfect system for a Corvette.

Alex

13 comments:

  1. You've got only an early-warming radar as a sensor, you'll need surface-search, fire-control- and helicopter-direction radars as well.
    There doesn't seem to be a sonar installed, on what info you're gonna use your torpedoes?
    No electronic-warefare suite?
    No decoys?

    I think the cost will go up ;)

    ReplyDelete
  2. How about http://theasiandefence.blogspot.com/2009/03/kri-frans-kaisiepo-368-sigma-class.html

    ReplyDelete
  3. Absent from the draft specification was communications / data fusion. Not certain if that was an oversight, or if it is something that everyone just assumes to be in place.

    My personal observation is that a netted architecture is invaluable when working with other ships, aircraft or sensors. It is a true force multiplier allowing one unit to share time/space/position data of the good and bad guys with others. Assume Link-16 at a minimum and maybe something more robust at the higher end.

    Other thoughts:
    1. 60 is too small a crew. Try a work force analysis with all of the funtionality that you envision and these guys will never sleep.

    2. Get rid of the helo.

    3. I like the USV, but there continue to be C2 issues with these guys: seemingly more complicated than a UAV to control.

    Bottom line: I like the idea of throwing out an idea like this. Great initiative.

    ReplyDelete
  4. Here my comments - sorry, but they're rather pessimistic.

    crew - likely much too small

    Range - this is unnecessarily long. This is not meant to be a cruiser, after all.

    guns - lacking a manually or remote-controlled autocannon or machine gun mount for very close encounters

    SSM - twice as many as the internationally agreed standard. You might consider the more modern and countermeasure-resistant NSM

    VLS - the long strike version, a questionable choice for a corvette

    triple torpedo launcher - (lightweight 324mm?) saving that (see your VLS remarks) won't save any significant sum. The launcher is cheap and used examples are in arsenals. You need the lightweight torpedoes anyway for the helicopter (that's imo the primary reason why these launchers are so common).

    Sensors in general - FFG/DDG equipment in a small corvette that's also stuffed with weapons; I feel that this isn't possible (also see: SAMs).

    Sonar - outdated afaik. An modern active low frequency VDS like LFTAS would be a much better idea vs. SSK.

    (LL)TV, IIR and LRF sensors - missing, but essential for object identification and passive surveillance

    Communications suite - missing

    ESM - is Vigile 400 only ESM? Modern ships of that size need ECM, too.

    SAM - that's the choice for an AAW DDG or FFG, not for a corvette. Mica VL, BAMSE and Barak

    SAMs are more suitable, or ESSM if an illumination radar capability is available

    Subroc - this is a sub vs sub weapon, I think you meant Asroc

    Boats - missing. Dinghy could be used as decoy especially with simple broadband ECM against home-on-jam missile modes, minimum: installation of decoy launcher and remote control/autopilot

    Propulsion - gas turbines aren't very efficient & never silent, waterjet isn't as efficient as propeller IIRC. Gas turbines produce a lot of exhaust gasses, pressing all that into the water is loud and means loss of efficiency (not advisable as permanent measure).
    I would rather choose a classic CODOG installation or a combined Stirling-electric engine with a propeller (not as efficient as diesel, but very silent) and a sprint gas turbine with forward/center waterjet.

    Hydrogen - no support infrastructure in harbors, no support capability in support ships, requires huge volume and lH2 limits mission endurance due to vaporization or requires a re-liquefaction system

    roll stabilization system - missing

    harbor maneuvering system - missing (a simple retractable fin in the path of a forward/center waterjet would do the job)

    external fire hose / fire fighting system / water projector - missing, but relevant for OPV use (I don't know the correct English word)

    cost - unrealistic unless you build hundreds of these in PRC


    overall - add 100 crew, another Lynx and 4,000 tons and you've got a GP DDG.
    You've stuffed too much into it for a corvette and neglected ASW (especially sound stealth) and unspectacular components.


    [I might have missed some vocabulary, German is my native language.]

    @Mr. Johnson: Helicopters are extremely versatile and useful. UAVs alone cannot cover the mission spectrum yet. Corvettes are not really a good choice in strong battlegroups and operate rather outside of friendly helicopter support.

    ReplyDelete
  5. Hey Alex,

    There's no way you'll fit all of this stuff on a 1500-2000 ton corvette. The equipment you've spec'd might fit on a 5000 ton frigate.

    Look at similarly-sized corvettes such as the German K130 for a reasonable configuration.

    The K130s cost around $300 million (USD) each, IIRC, so I think your estimated price is low.

    ReplyDelete
  6. If you drop the VLS, the rest might fit. A warship can expect to carry 5-10% of it's light ship displacement in payload. If your corvette's light ship is 2000 tons, then that means 100 to 200 tons of payload. A loaded, 32 cell Mk41 VLS weighs around 100 tons by itself! (for comparison, a RAM launcher only weighs around 6 tons)

    Plus a strike length cell is 25 feet long, which will be tough to fit in a small hull, especially 24+ of them.

    ReplyDelete
  7. A 2800 ton light ship means over 3000 tons full load. Certainly this is more reasonable for a VLS, though there aren't any ships of this size with 24 or more Mk 41 cells.

    This is roughly the same size as a Type 21 frigate, btw.

    IMHO, a reasonable armament for a future British 2000-2500 ton (full load) "corvette" would look something like this,

    - 1 gun (whatever the RN wants in this class)
    - 8-16 Slyver A43 cells with Aster 15 & CAMM quad-packs
    - 8 x Harpoon
    - 1 CIWS (or additional A35 cells for CAMM)
    - 2 x 30mm guns
    - triple torpedo mounts (though one US Admiral said you might as well add a lifeboat launcher rather than torpedo mounts these days because if you're in range to use them, you're about to eat a torpedo)
    - 1 Lynx-sized helo pad and hangar

    Just MHO.

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  8. I chose Slyver only because the RN chose it for the Type 45. Being American, I certainly think Mk 41 is preferable, but the UK has hitched its horse to the Aster/Slyver wagon. It doesn't make sense to change for this class.

    A 3000+ ton ship could carry a small number of Slyver A70 cells, if you really, really want TLAM. Personally, I don't think it's worth the weight and cost for a low-end frigate.

    How has Absalon shown that it needs more than 8 x AShMs? Has it fired any? It gets a lot of use out of its helos and boats in CTF 151, but hasn't had to fire a shot of any sort in anger, AFAIK.

    VL-ASROC is certainly an improvement over triple mounts over the side, but a torpedo-armed helo betters both. Until someone produces a UAV with a dipping sonar that can carry torpedoes (not to mention perform SAR), I'll stick with the manned helo.

    Alex, I get the impression that you want to build a frigate here. Area air-defense, long-range surface strike and high-end ASW really aren't tasks for a corvette.

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  9. Alex,

    It doesn't feel like a good idea to have multiple, similar VLS systems in service. You won't maximize your R&D money spent on integration, and will have yet another unique system to support. That being said, if the RN decides to go with Mk41 for future Type 45s, then by all means, use it here too.

    The RN also doesn't use VL-ASROC, so that would be another new system.

    I wouldn't expect a corvette-sized vessel to be a primary TLAM shooter. A ship of this size will likely only have 8 or 16 strike-length cells (and only if you make sacrifices elsewhere), some of which will have to carry ESSM, VL-ASROC or SM-2. So just carrying 2 or 4 TLAMs isn't much help, IMHO. Better to let your big ships carry TLAM in larger numbers.

    Size is not the major cost driver in warships. "Steel is cheap and air is free", as they say. The big cost driver is the desire to pack a ship full of expensive combat systems. You can have a larger ship if you exercise restraint and keep the combat systems to the bare minimum. A larger ship has more room for upgrades over its lifetime, handles rough seas and combat damage better, and is generally more comfortable for its crew.

    I'm not sure which UAV you mean. The one I've seen mentioned for the K130 is the S-100 Camcopter, which is way too small to carry torpedoes or a dipping sonar. Firescouts may one day carry a dipping sonar, but they are too small to carry current generation torpedoes. They may one day carry the smaller torpedoes under development.

    Regardless, a manned helo is still more flexible. You can't do this,

    http://www.aiai.ed.ac.uk/project/cosar-ts/img/uk-sar-3-600x800.jpg

    with a UAV. At least not yet.

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  10. Thales integrated sensor mast
    http://www.youtube.com/watch?v=8sMgEsHC1Lc

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  11. Hi Alex,
    My overall impression is thus: the Corvette seeks to do too much for its role, especially given the expected price.

    I think that the real thing that needs to be considered first here is the expected missions for this vessel.

    Given your profile (weapons loadout, range), you effectively want a miniature Cruiser (WWII definition). The problem of Corvettes, as much as I love them, is that they are not meant to operate that far out from other forces. They can patrol coastal regions quite well and complete transatlantic transits as escorts, but they're not meant to be the do-all warship.

    In terms of mission priorities, a 2000t Corvette is light for what you seem to be looking for in a vessel. The loadout is more along the lines of a light frigate (Danish Huitfeld) as it far exceeds the systems of the fairly heavily armed K130-class corvettes.

    You can make a small, heavily armed warship, but it will have sacrifices in top speed, weight and range beyond what are noted. A 10,000nm range would require a vessel with extremely efficient engines and very few weapons or topside systems for its mass.


    I like a lot of the design features you've considered (modest speed, compact but not miniscule crew, displacement range and the inclusion of basic outer surface shaping for basic signature reduction).


    I think that the ASM armament is heavy for a balanced vessel and that, given lack of a US-centric systems basis (with which we have to contend over here), you might look to alternate missile systems.

    Without much of a change in weight, you might replace the Harpoon ASMs with something like Kongsberg's NSM. The NSM is essentially a late-90s/early-00s reimagination of the high-subsonic ASM.

    Versus the Harpoon, the Naval Strike Missile has:
    - A stealthier form
    - Is lighter (412 vs. 691kg)
    - Faster (0.9+ vs. 0.71 Mach)
    - Has a smarter guidance package (inertial, GPS, terrain-reference navigation, imaging infrared homing, target database vs. inertial guidance, radar-altimeter and active radar)
    - A longer range (200+ vs. 124km according to deagel)
    - Superior terminal maneuvering for evasion of hard kill defenses.

    The NSM is also capable of dealing with complex terrain (littorals) and is programmable to 200 waypoints (so it can fly through and between islands en route to its target), so it could be used both in Blue Water and Littoral operations.

    The drawback is a smaller warhead (120 vs. 224kg), but the improvements are worth that.

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  12. Ultimately, you will also need to make some decisions about what systems you WANT vs. what systems you NEED. It's nice to have a lot of VLS SAMs available, but a full Mk41 VLS system is tremendously heavy for such a craft. Smaller VLS systems (such as for the Sea Sparrow) or shorter variants of the Mk 41 might be better, especially if the desire is AD (4 ESSM/tube makes the weight worth it, but then you need a director).

    One caveat, however, is that a smaller (Sea Wolf/Barak/Mica/etc.) type VLS SAM might be better for the lighter vessel. Capable of short-range AD (really a point-defense), these systems are quite compact and relatively light. The radar directors for these won't cause the top weight issues of the radars necessary for the ESSMs.

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  13. My view on it:

    Revised Ship Specs:
    L: 95m
    B: 11m
    Displacement: 2200t(onnes), full.
    R: 6,000nm@14kt
    Max Speed: 28kt
    Crew: 54 ship's crew, 12 airwing
    Passengers: 16-20
    Shaped hull and superstructure to minimize RCS.

    Revised Weapons Layout:
    Foremost: 57mm
    Second (elevated): 35mm CIWS
    These two guns are placed similarly to the Gun and RAM on the K130s and Huitfelds. This allows for your desire to

    (Superstructure of bridge, sensor mast, etc.)
    On superstructure (mid): mini-VL SAMs (2x32)
    Aft of miniVLS: Harpoon/NSM Launchers (2x4missiles), 4-pack launchers normally flat with deck, one end is elevated into firing position.

    (Below deck level: six 324mm mk32 torpedo tubes, 3 mounted within the hull on each side, as on the Eilat (Sa’ar 5) class)

    Stations on each side with 25-30mm gun, on superstructure. Could be Mk 46 Mod 1 weapons station (reload internal to the vessel) or Typhoon-like RWS.

    (end superstructure in hangar)
    On hangar: 35mm CIWS, 2 more RWS at deck level.

    Landing Pad.

    Near waterline, a boat deployment system similar to that of the Absalons, but sized for RIBs/CRRC. This would give the vessel some additional capability to support VBSS teams.


    If you’re willing to give up the forward Millennium gun, the 64 VLS can be shifted up there and more ASMs could be added (or the vessel could be shortened by a few meters and the displacement reduced slightly to match).

    Now, there is also another option. Given that this is supposed to be a corvette for the UK, the best bet might be to get VT to build a larger (stretched) version of the Qahir class corvette.

    Best,
    CBD

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