Moderator: Community Manager
[Post Reply] [*]  Page 13 of 14  [ 135 posts ]  Go to page « 110 11 12 13 14 »
Author Message
r3mu511
Post subject: Re: Notional 9000tFL USN FFG with THE POWER OF THE ATOMPosted: July 27th, 2016, 11:49 am
Offline
Posts: 31
Joined: June 11th, 2016, 2:27 pm
erik_t wrote:
One USN FF (I forget which) replaced SPS-40 with Mk 23 for testing in the 1980s and never switched back.
yup, that was the knox class ff-1070 "Downes", which served as the test ship for the 1975 at-sea testing of the TAS mk23...


Top
[Profile] [Quote]
erik_t
Post subject: Re: Notional 9000tFL USN FFG with THE POWER OF THE ATOMPosted: July 27th, 2016, 9:39 pm
Offline
Posts: 2936
Joined: July 26th, 2010, 11:38 pm
Location: Midwest US
Thanks, that's the one. A little earlier than I'd thought.

So let's not pretend the L-band arrays are a fabulous earthshattering inclusion (I waffle on declaring them IFF-only), but they might at least force the other guys to pay lip service to LO design at longer wavelengths. And frequency diversity is never, ever a bad thing in the face of ECM.


Top
[Profile] [Quote]
erik_t
Post subject: Re: Notional 9000tFL USN FFG with THE POWER OF THE ATOMPosted: August 7th, 2016, 8:57 pm
Offline
Posts: 2936
Joined: July 26th, 2010, 11:38 pm
Location: Midwest US
Having defended my thesis finally (woo!), I had time to do a little bit of drawing/bashing this afternoon as something to directly enjoy, rather than as something to temporarily reduce stress.
  • The Rheinmetall MLG-27-mounted lasers are not necessarily superior to domestic tech, but they are much more easily scaled for drawing. The little beam turrets can definitely fit a 40kW installation, which is approaching something really quite useful.
  • Further fiddling with stupid little stuff. The emergency conn aft has an 18" Furuno nav set on the OE-538 radio mast, forward of the aft main satcom. The boarding platform is shaped for better RCS. Slight shading changes at the bow and stern.
  • I don't remember if I specifically called it out before or not, but I moved away from Mk 57 VLS, in favor of a cold-launched system perhaps adopted from a concept Northrup-Grumman has been floating (pdf warning). This offers 120 Mk41-equivalent cells, 96 Mk57-equivalent, 72 32"-interior-diameter canisters, or some blend thereof.
  • This offers the capability to move well beyond puny 21"-diameter SM-3 Block IIA and its weak-ass 4.5km/s burnout velocity, toward something that probably offers actual factual defense against ICBMs. I leave further description intentionally vague, although I also present a Conventional Prompt Global Strike derivative.
[ img ]
[ img ]
I think that's it for changes to the DDGF variant.

The CGF (maybe CCGF at this point?) got a little longer, to improve the boat disposition. The constant-section plug is now 16.5m or thereabouts, a 15m compartment and 1.5m-ish cofferdam.
  • We now can fit an 11m RHIB or equivalent in the starboard bay, and a 9m or equivalent (presumed to be a plush boat for the flag officer) in the port bay.
  • There is now a third major satcom and two medium units amidships, which is a much better jump in capability.
  • As a consequence of the satcom refiguring, the flat bridge is now even less able to accidentally interfere with the actual operation of the ship by seeing what is going on. Gee, whoops.
[ img ]

I've been getting chatter from some buddies that they absolutely demand bridge wings, rather than the Zumwalt-y open-windows solution. It is under consideration.


Top
[Profile] [Quote]
r3mu511
Post subject: Re: Notional 9000tFL USN FFG with THE POWER OF THE ATOMPosted: August 8th, 2016, 9:46 am
Offline
Posts: 31
Joined: June 11th, 2016, 2:27 pm
(tech OT: sm3-blk-2A)

fwiw, this 2011 FAS report on bmd (ref: http://fas.org/pubs/_docs/2011%20Missil ... lowres.pdf) credits sm3-blk-2A with the ability to offer post-midcourse, pre-reentry ICBM intercept capability with burnout velocities even as low as 4.0 km/s (high-end estimates of it's Vbo is 5.5 km/s)... although not delved into in depth in the report, the MDA diagram used (p.28) also indicates a post-boost, pre-midcourse, exo-atmospheric, ascent phase intercept capability for blk-2A...

interestingly if one follows the MDA update reports, this limited ICBM intercept capability has been de-emphasized in later reports (see http://mostlymissiledefense.com for an archive of MDA reports), perhaps to assuage russia of their fears of having Aegis Ashore deployed in poland and romania as part of the EPAA since blk-2A is a planned upgrade path for the ashore sites as well...

as the FAS report stresses though, ICBM countermeasure decoys are a whole different matter (beyond an interceptor's Vbo rating) once an ICBM has achieved exoatmospheric altitude...


Top
[Profile] [Quote]
erik_t
Post subject: Re: Notional 9000tFL USN FFG with THE POWER OF THE ATOMPosted: August 8th, 2016, 9:30 pm
Offline
Posts: 2936
Joined: July 26th, 2010, 11:38 pm
Location: Midwest US
Yeah, it's fuzzy (at least in the open literature) just how capable Block IIA might be in intercepting more energetic and longer-ranged targets, or what the burnout velocity might be. I was taking 4.5km/s from some mid-1990s Navy-supported work that suggested it would be possible to provide terminal defense of the entire CONUS from shipboard platforms (presuming one could puddle around Lake Superior). I too am cribbing from MMD, which I do not consider absolutely authoritative or wholly without bias, but it's definitely the best resource around.

You are quite right to note that there is more to the intercept problem than total dV. One might imagine an interceptor boost vehicle that carries a bigger, angrier, better-shielded, better-sensors EKV than SM-3 IIA, rather than going for absolute maximum burnout velocity. It seems shrug-your-shoulders likely that the optimum solution is somewhere in between; the point of the effort was to provide a mass and dimensional envelope beyond what can be offered by Mk 41 or even Mk 57. Whatever is the most capable possible booster design, we can be sure that it is larger and heavier than anything you could reasonably deploy aboard even a 15kton destroyer. Whatever is the most optimum system design, it's best to provide a relatively flexible GMLS so as to integrate as many of the missiles as possible.

Plus the whole CPGS mission, which as far as I'm concerned might even require a KEI-class vehicle. Whatever it needs, it probably needs more.

Finally, cold-launch VLS is just prettier :P


Top
[Profile] [Quote]
r3mu511
Post subject: Re: Notional 9000tFL USN FFG with THE POWER OF THE ATOMPosted: August 9th, 2016, 1:18 am
Offline
Posts: 31
Joined: June 11th, 2016, 2:27 pm
erik_t wrote:
... suggested it would be possible to provide terminal defense of the entire CONUS from shipboard platforms (presuming one could puddle around Lake Superior)...
probably from this 1992 image:

[ img ]

also in: http://marshall.wpengine.com/wp-content ... System.pdf, and discussed in mostlymissiledefense some time ago... this image is also post-midcourse, pre-reentry intercept...


Top
[Profile] [Quote]
erik_t
Post subject: Re: Notional 9000tFL USN FFG with THE POWER OF THE ATOMPosted: August 9th, 2016, 1:51 am
Offline
Posts: 2936
Joined: July 26th, 2010, 11:38 pm
Location: Midwest US
That's one of said images, yes. I think there was another one, but the specifics maybe aren't critical. This is characteristic of the capability we might expect from a IIA-class booster, whether or not it's exactly right on the fringes.


Top
[Profile] [Quote]
citizen lambda
Post subject: Re: Notional 9000tFL USN FFG with THE POWER OF THE ATOMPosted: August 10th, 2016, 10:33 pm
Offline
User avatar
Posts: 467
Joined: March 2nd, 2016, 8:30 pm
Looking good as always.
Can't fault you for moving to cold-launch VLS with such a design, IMO it helps saving hull space with peripheral cells and should have been introduced much earlier "MLS is based on the same technology as the Trident II launch system" indeed, as if there was anything new with cold-launch...
But maybe I'm biased by my current Russian slant though :)
BTW, is your fusion plant water-based to any extent? Otherwise you might have to figure out some additional gas generation system for the VLS. While we're at it, how far-fetched would it be to use the huge power reserve for some kind of EM-VLS? Use a linear drive to push the backplate below the missiles? Can't be much harder than EMALS, can it?

Regarding your larger VLS cells:
- From the missiles you show, I assume that your CPGS missile is based on the same envelope as your sorta-KEI? Does that mean you are shooting for a pure KE effector?
- In terms of mission, is this something you would need to carry on a DDG? Not that you would necessarily be able to segregate between missiles once the cells are in place. Expect political fallout big time when you start deploying that kind of platform. This is part of what killed CPGS in the first place.
- Northrop's tech sheet leaves me hanging about the level of in-service modularity. Depending on how easy you can change the different cell volumes, you might want to dedicate a small part of the array to the larger missiles.
- Just throwing this out here since it isn't really on topic: Your "heavy" missiles focus on acceleration so far for range or interception dV. How about payload? Have you given any thought yet to larger cruise missiles or long-range loitering UAVs fired from these larger cells?

_________________
Soviet Century/Cold War 2020 Alternate Universe: Soviet and other Cold War designs 1990-2020.
My Worklist


Top
[Profile] [Quote]
erik_t
Post subject: Re: Notional 9000tFL USN FFG with THE POWER OF THE ATOMPosted: August 11th, 2016, 12:09 am
Offline
Posts: 2936
Joined: July 26th, 2010, 11:38 pm
Location: Midwest US
citizen lambda wrote:
Looking good as always.
Can't fault you for moving to cold-launch VLS with such a design, IMO it helps saving hull space with peripheral cells and should have been introduced much earlier "MLS is based on the same technology as the Trident II launch system" indeed, as if there was anything new with cold-launch...
But maybe I'm biased by my current Russian slant though :)
BTW, is your fusion plant water-based to any extent? Otherwise you might have to figure out some additional gas generation system for the VLS. While we're at it, how far-fetched would it be to use the huge power reserve for some kind of EM-VLS? Use a linear drive to push the backplate below the missiles? Can't be much harder than EMALS, can it?
I presume liquid cooling for the reactors, yes. I figured the cold-launch cells were something akin to an automobile airbag, with a small fast-burn charge at the bottom, rather than leveraging any sort of shipboard services for launch. I think you probably could do something electromagnetic, but that starts feeling sort of dubious to me financially. We might realistically expect a destroyer VLS canister/cell to fire a round maybe five or ten times over the life of the ship... I don't see the longevity gains of E&M being at all worth it here.
Quote:
Regarding your larger VLS cells:
- From the missiles you show, I assume that your CPGS missile is based on the same envelope as your sorta-KEI? Does that mean you are shooting for a pure KE effector?
- In terms of mission, is this something you would need to carry on a DDG? Not that you would necessarily be able to segregate between missiles once the cells are in place. Expect political fallout big time when you start deploying that kind of platform. This is part of what killed CPGS in the first place.
Good questions, to which I don't have the answer.

On the former, yes, I'm presuming something of the same scale, and maybe even leveraging the same lower stages, as super-Standard. I don't think it's necessarily a DDG mission to carry these sorts of weapons per se, but an increased number of potential platforms carries with it the dual benefit of a decrease in maximum range required and a decrease in reaction time from the nearest regional platform to the sudden-onset target.

The political observation is astute. It's possible to imagine a scenario where you keep far, far short of a dual-key approach, but in which major regional powers are kept apprised of which systems are onloading and offloading for, gee just spitballing here, tooling around the Indian Ocean and Persian Gulf. I don't think local powers would be perturbed or perceive it to be destabilizing to have the ability to, say, cave in a single cave in some nebulous tribal region, but it would definitely seem problematic to have tons and tons of the things. Perhaps you might have the VLS cell-block doors be a replaceable item sized for the boosters within, so that neutral satcom could keep regional powers apprised of what systems are deployed where? Just thinking out loud here.
Quote:
- Northrop's tech sheet leaves me hanging about the level of in-service modularity. Depending on how easy you can change the different cell volumes, you might want to dedicate a small part of the array to the larger missiles.
I think the PDF is talking about two flavors of systems, though they don't come right out and say it. One system is for six-into-eight drop-in Mk 41 replacements without much growth margin (maybe to Mk57-size), whereas the other system envisions wide cutouts through the hull girder, with much more flexible loadout. I suspect this latter system would not be a drop-in Mk 41 replacement without extensive structural modifications, and maybe not even then. But I'm an aero guy, not a structures guy ;)
Quote:
- Just throwing this out here since it isn't really on topic: Your "heavy" missiles focus on acceleration so far for range or interception dV. How about payload? Have you given any thought yet to larger cruise missiles or long-range loitering UAVs fired from these larger cells?
I've personally mused on it, but I sort of leave the implications intentionally vague. It's not at all hard to imagine development of strategic systems like ABM or CPGS that are accidentally (or intentionally) limited to a specific number of platforms, especially when the mission simply cannot be achieved on a smaller size. Something like a UAV, though... do you want to blow that sort of cash on a system that won't be deployable on the dozens of Burkes that would surely be in service for decades? Do you gain that much compared to something like ScanEagle or similar, especially when we have these huge mission bays anyway? And of course you're totally throwing away FMS possibilities, with the entire western world centered around ~21"-class Mk 41 and Sylver.

These questions are unanswerable, so I shall not try! But it is very interesting to think about. I would bet a large bag of nickels that the USN has done at least preliminary studies of what quad-packed vertical launch system you might be able to fit in the SSGN/Virginia Flt-III payload tubes. Future-proofing is important.


Top
[Profile] [Quote]
citizen lambda
Post subject: Re: Notional 9000tFL USN FFG with THE POWER OF THE ATOMPosted: August 11th, 2016, 9:10 pm
Offline
User avatar
Posts: 467
Joined: March 2nd, 2016, 8:30 pm
erik_t wrote:
I presume liquid cooling for the reactors, yes. I figured the cold-launch cells were something akin to an automobile airbag, with a small fast-burn charge at the bottom, rather than leveraging any sort of shipboard services for launch. I think you probably could do something electromagnetic, but that starts feeling sort of dubious to me financially. We might realistically expect a destroyer VLS canister/cell to fire a round maybe five or ten times over the life of the ship... I don't see the longevity gains of E&M being at all worth it here.
I guess you're right... Must still be stuck on the early Soviet revolver VLS, where only one tube would launch all the missiles in one pack and it made sense to invest in a more sophisticated launch system. Honestly, the EM VLS thing was completely over the top to start with.
I must say I really like your airbag concept of hot-launch-in-a-can, since you can directly fit the charges inside the individual canisters.
My personal reflections had landed me on a compromise with a single compressor/gas tank per VLS silo (8 cells or above) with a switch valve to shunt gas loads to secondary tanks below each cell in turn. But again, Russian design bias, that version makes more sense based on an older cold-launch culture.
erik_t wrote:
Good questions, to which I don't have the answer.

On the former, yes, I'm presuming something of the same scale, and maybe even leveraging the same lower stages, as super-Standard. I don't think it's necessarily a DDG mission to carry these sorts of weapons per se, but an increased number of potential platforms carries with it the dual benefit of a decrease in maximum range required and a decrease in reaction time from the nearest regional platform to the sudden-onset target.
No problem with that, though it opens the question of the modularity of the VLS system. If it is only modular during build-up and you can't swap module types pierside, you might want to reduce the payload of your DDG to Mk.57 envelope, or reduce the amount of heavy tubes.
Also q.v. below for the political impact.
erik_t wrote:
The political observation is astute. It's possible to imagine a scenario where you keep far, far short of a dual-key approach, but in which major regional powers are kept apprised of which systems are onloading and offloading for, gee just spitballing here, tooling around the Indian Ocean and Persian Gulf. I don't think local powers would be perturbed or perceive it to be destabilizing to have the ability to, say, cave in a single cave in some nebulous tribal region, but it would definitely seem problematic to have tons and tons of the things. Perhaps you might have the VLS cell-block doors be a replaceable item sized for the boosters within, so that neutral satcom could keep regional powers apprised of what systems are deployed where? Just thinking out loud here.
Guess you can signal the presence of a certain type of payload in the tubes like you describe, though you might need something more phyically constraining to make deception impossible. E.g. an enlarged and color-coded tube cover on the CPGS canisters, because the missile is longer than the KEI and doesn't fit in the standard cell. Of course, the viability of that part is only as good as your country's inability to circumvent that limitation, and not everyone gets given the benefit of the doubt in that case. See the debate a few years back about Iranian miniature nuke design and the nuclearization of their SRBM arsenal. Just because you can do something doesn't mean you are actually doing it, but it does mean that you can't be trusted not to do it.

Your version here is actually different from the original CPGS proposals in that neither the vector or the platform are derived from a nuclear baseline (see SSBN/Trident for CPGS), so there is no initial assumption that every shot can be a nuke. OTOH, any land-attack CPGS spin-off of some full-bore KEI is in effect a high-end IRBM, and nothing prevents you from fitting a nuke in there.
Once you get there, it isn't really about busting a cave here and there but about 1) the growth potential of your platform and 2) upsetting the sub-strategic deterrence balance in a given area.
For this one, see the Russian reaction the TBMD/Aegis Ashore deployments in its strategic backyard and the counter-deployment of Iskanders on the borders. In this case, no one (serious) invokes actual offensive intent from the other sides, but seeks cover their bases to de-incentivize escalation at/beyond a certain threshold. Now consider one of your DDGs/CGs armed with both potentially-nuclear IRBMs and high-end ABMs puttering around in the Black Sea and you'll have a glimpse of the potential for destabilization. Heck, even a single CPGS can end your regime, nukes or not. A Tomahawk too, but current COTS tech can protect you from those, while a reliable export-version IRBM-killer is still some ways off.
Beside that, your diplomatic problem is compounded by the USN's policy of not declaring their nuke deployments, which presumably extends to other munitions. Even if they were keen on that, the logistics of publishing loadout manifests before sailing would be complicated by the unpredictability inherent in any warship deployment.
The gist of the problem is actually the very modularity of the VLS system. Once another country forces an IRBM-free zone upon you, let alone a nuke-free zone, you either submit to a very intrusive inspection regimen every time you sail in to ensure your ships are nuke/IRBM -free, or you just don't deploy there.
erik_t wrote:
I think the PDF is talking about two flavors of systems, though they don't come right out and say it. One system is for six-into-eight drop-in Mk 41 replacements without much growth margin (maybe to Mk57-size), whereas the other system envisions wide cutouts through the hull girder, with much more flexible loadout. I suspect this latter system would not be a drop-in Mk 41 replacement without extensive structural modifications, and maybe not even then. But I'm an aero guy, not a structures guy ;)
Welcome to the club ;)
From what I can gather though, there doesn't appear to be any supporting structure inside the volume of a 61- or 29-cell Mk.41 block. Which means that you can drop in (at refit level, obviously) other cells with the same volume envelope, as long as you don't exceed weight and height margins.
BTW found a very interesting discussion on another board about the genesis of the Mk.41 and this very weight/height issue, which sheds a light on the potential for exceeding margins in this context.
erik_t wrote:
I've personally mused on it, but I sort of leave the implications intentionally vague. It's not at all hard to imagine development of strategic systems like ABM or CPGS that are accidentally (or intentionally) limited to a specific number of platforms, especially when the mission simply cannot be achieved on a smaller size. Something like a UAV, though... do you want to blow that sort of cash on a system that won't be deployable on the dozens of Burkes that would surely be in service for decades? Do you gain that much compared to something like ScanEagle or similar, especially when we have these huge mission bays anyway? And of course you're totally throwing away FMS possibilities, with the entire western world centered around ~21"-class Mk 41 and Sylver.
Not sure the deployability of that notional insta-UAV would be that limited. If (let's go wild here for a second) your heavy VLS is in the same envelope as a Trident tube, you could back-fit all of its payload to, say, an Ohio SSGN, maybe a Virginia B3 if length allows, or some future compatible SSGN. With the appropriate underwater-launch tube, the UAV becomes something that can be deployed anywhere from dozens of platforms. Leaving aside that it can't be that hard, in a +10-20-years timeframe, to dig out the Mk.41 pits of the newest Burkes around and retrofit them with your modular VLS.
Also I don't think I'm too way off course imagining a true HALE UAV fitting in that envelope? Maybe a puff-up aerostat-hybrid design with solar backup, it could be held aloft for weeks, and a short full-bore KEI booster segment could conceivably lift it up to around 100kft and/or a few hundred of miles off course. If that's too expensive, land it back on a carrier, pack it back up in the weapons shop and VERTREP it back to the right ship :lol:
All in all, there's value to be had, but all that stuff makes all the more sense with each payload and vector you add.

_________________
Soviet Century/Cold War 2020 Alternate Universe: Soviet and other Cold War designs 1990-2020.
My Worklist


Top
[Profile] [Quote]
Display: Sort by: Direction:
[Post Reply]  Page 13 of 14  [ 135 posts ]  Return to “Personal Designs” | Go to page « 110 11 12 13 14 »

Jump to: 

Who is online

Users browsing this forum: No registered users and 17 guests


The team | Delete all board cookies | All times are UTC


cron
Powered by phpBB® Forum Software © phpBB Limited
[ GZIP: Off ]