By the light of Green Flax, what happens next

zen

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Assuming the RN does select Green Flax aka Thunderbird II instead of Sea slug for the County class Destroyers, the early obsolescence of the ships is no longer a given.

In that light, what happens to the Type 82 Destroyer design process? Does this simply become a 'all-GT' version of the County class? Or perhaps continues to become a 'new ship' but using the Thunderbird II SAM.

Assuming the Type 82 still dies, can we fit a navalised Thunderbird to a smaller ship like the Type 42?

In fact in that light do we see SIGS continue as a UK 'Tartart' type SAM system? Say as SIGS-16.
Does this alter the PT.428 story and the ermgence of Sea Wolf and Rapier?

And what impact does that have on Frigate design processes?
IF in turn SIGS-16 is developed, this is applicable to something like a Frigate.

And if we see SIGS remain, then surely this incrases the logic behind SHIELD using SRAAM?
Which takes us back to Rapier alternatives....
 
zen said:
Which takes us back to Rapier alternatives....

Us? Just you are on that trip I think.

Thunderbird 2 in place of Sea Slug has little effect on the requirement for Sea Dart. It was designed to be a maintenance free, compact missile. And Thunderbird would be just as big as the Slug. The Type 82 grew to be the size of the County because it was to have a big 3D radar and data systsm. When the contemporary system was considered for the County it would have required the removal of its guns and standoff ASW. Things the T82 could have in addition to the high end AAW system.
 
A mere term of speech, inclusive on context. If you do not wish to be included, that is your choice.

Granted Thunderbird is large, but the mkii is more effective than Sea Slug thanks to greater range, and therefore viable for a longer period.
Consequently the drive and desire to replace it and in turn replace the County class is less.

So in this light the need for Sea Dart is less.

Now it maybe arguable that under such circumstances Sea Dart as we know it might still emerge, but it's not so clear it will do so as quickly.

Equally in the light of a more potent AAW system as Thunderbird II offers, the need would be less for the long range missile, since NIGS would be it's initial successor, while SIGS could remain as a cheaper, lighter and shorter ranged system.
In fact cosnidering the Thunderbird missle, there is quite some scope for a mkIII, using more modern electronics, and rocket motor and a single booster.

Remember the SIGS-16 design, permits a more efficient packaging of electronics and it's guidance requires less power. Consequently a SIGS-16 system is highly likely to be smaller overall in terms of impact on the ship, compared to Sea Dart.
 
Abraham Gubler said:
Thunderbird 2 in place of Sea Slug has little effect on the requirement for Sea Dart. It was designed to be a maintenance free, compact missile. And Thunderbird would be just as big as the Slug. The Type 82 grew to be the size of the County because it was to have a big 3D radar and data systsm. When the contemporary system was considered for the County it would have required the removal of its guns and standoff ASW. Things the T82 could have in addition to the high end AAW system.

Forgive me if I'm wrong, but wouldn't the proposed naval version of the Thunderbird II system actually have been somewhat more compact than the Sea Slug installation, both in terms of missiles/handling equipment and of radars e.g. the navalised GREEN GINGER suite (whatever it's Rainbow Code was)? Not to mention that the overall Sea Slug system ended up being neither compact nor maintenance free.
 
JFC Fuller said:
Sea Dart's development was independent of any issues around Sea Slug, the former was its own independent frigate specific requirement and not influenced by Sea Slugs performance. Choosing Green Flax would have had no impact on Sea Dart development.

Not quite correct that. SIGS starts off as a yes a Frigate or Destroyer system, it's relationship is clear with NIGS. One the heavy long range system, the other the light short range.
It's once they consider fitting a ramjet instead, they realise they can get Thunderbird-like range on a weapon much smaller. NIGS falls apart due to it's costs/complexity, SIGS grows into the CF.299 concept.

So yes SIGS doesn't directly continue from Sea Slug, rather NIGS does. SIGS evolves, NIGS dies, and SIGS ends up a much longer ranged system, requiring extra power and I suspect complexity.

However, in the context of pursuing Thunderbird II instead of Sea Slug. Elements of NIGS are clearly applicable, such as the seeker, Type 985, ADAWS and possibly the TIR.
Considering that NIGS was viewed as a follow-on from Sea Slug and would start life initially on a version of the County (this fell apart of course once they tried to fit 985 as well).
Eventually 985 will die the death,988 will arise and possibly also die the death save for the Dutch carrying onward.
But the seeker, illuminator, and ADAWS are strong contenders to continue considering they will deliver much improved performance for Thunderbird III.
As would improvements to the rocket motor, aerodynamics and booster.
All of which make more sense since they are more applicable to Thunderbird than Sea Slug.
Strengthening the case to continue with the County class for longer, avoiding their premature retirement and in turn delaying their direct replacement.

Type 82 'as is' tried to become their replacement, hence 988, CF.299, ADAWS etc....

In this scenario, however....Type 82 could end up with SIGS-16 (or Tartar), and might be end up being built later on with an all GT propulsion set.
 
Type 82 grows out of a SIGS armed Leander concept aimed at mas production for low cost. It becomes, along with CVA-01 and a number of other projects anything but mass producible, due to the rising costs of a increasingly complex ship.

It reasonably clear, that in the light of Countys able to be upgraded beyond Thunderbird II to a mk III, that the area air defence needs, need not be met by SIGS.

Interestingly enough the 20.75inch diameter of Thunderbird is sufficient to take a dish of great enough diameter which would permit Sea Dart type guidance of a so modified missile. At least as far as the RN claimed to the Dutch.

However.....SIGS came down to a choice between boosted PT.428 and CF.299. Both at the time of decision using quadruple launchers.
Considering this PT.428 is potentially a dual service system, and notably lighter.
 
It doesn't matter how you word it, Sea Dart was designed to the original SIGs (the requirement had a number of earlier incarnations) requirement, the success or otherwise of Sea Slug and then NIGs had no bearing on its capabilities.

As far as the RN was concerned there was no choice between Sea Dart and PT.428, they regarded the latter as performing the same role as Sea Cat. PT.428 was lighter because it was a different class of missile and didn't meet the small ship weapons system requirement.

Type 82 was a dedicated Leander replacement, everything on it was what the RN had wanted on such a ship, it did not grow due to the abandonment of NIGS.
 
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This is the alternative history section.
And in this particular alternative history scenario the basis for it's being alternative is the RN going for Green Flax aka Thunderbird II rather than Sea Slug.

The idea this exerts no influence is false.

Under the environment in which the RN is pursuing Thunderbird II and a possible mkIII on upgraded Countys, what is the point of SIGS 'as is'?

I can see an argument for a larger (than seadart) ramjet missile to succeed Thunderbird II.

Indeed in this environment, what is the point of SIGS, when you can buy Tartar?
Why allow funds to be drained away from Thunderbird II and mk III, applicable to ships already being built, for a missile system that won't enter service for a decade?

As you yourself point out, it's no successor to Sea Cat. Not cheap enough or light enough. And in fact once the studies into 'cheap CF.299 frigates hit their inevitable conclusion, why continue with it 'as is'?

It's not for area air defence anymore, that is now covered by Thunderbird II, NIGS or a mk III.
It's not a PD system, that's currently Sea Cat and could be PT.428.

Cheaper is Tartar, and that is pursue-able as a license system. In fact one can even envision a UK version of Tartar, which not only helps get around the issues of supply, but includes the RNs perfered systems. Unlikely to exceed Sea Darts 1,200lb weight.

Curious sidetrack, Blue water evolves from Red Rose, a nuclear warhead on a surface to surface missile packaged inside a Thunderbird airframe.
 
So speculations.

Can one fit Type 988 to the County type ? It's the question that would be asked in the period.

How much more of a Frigate could something with Sea Slug or Thunderbird II be. I think there is some design of a Sea Slug Frigate I've seen somewhere in my readings.
 
resurrected thanks to reading Postwar Naval Revolution.

'56 Green Flax option was looked at in the view of USN favouring manual fitting of fins prior to launch.
Since Thunderbird was designed to be assembled in minutes.

So potential for more storage.
Space for 64 Sea Slug, would allow 25 ready to use and 70 broken down for assembly.
In a space for 48 fully assembled weapons some 64 could be stored without fins...
 
Looking at the dimensions of Thunderbird and Seaslug, both the fin diameter and the body diameter of the "bare" missile (devoid of boosters) are greater for Thunderbird, making me wonder how much work would be needed to bring Thunderbird "aboard" and whether this would be worth it. And that's before we get to the span of the fins on the boosters and the work required to navalize the weapon.
 
SARH has pluses and minuses in it's favour. Ranges beyond 50nm, some 20nm more than Sea Slug mkII. System Target tracking out to 110nm.
Type 86 is lighter than Type 901.....substantially so.

Diameter 21" verses....err..16"? Or is it 14"? I forget.

Launcher is ideally the twin arm sort.

On the face of it, less ready to use missiles but more in storage and quick to assemble.

Impact, no polyrod SARH, 18" room for nuclear warhead. Range potentially extendible much further with better motors.
Packaging Command Guidance easier.
NIGS process more achievable even at sacrifice of PESA array.
Rail launcher permits alternative scheme missiles.
 
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