Originally Posted by
SLXOwft
I referred to the Type 12 (one could even go back to the 41/61s) as I saw them as a paradigm for a basic design being modified as role, needs and technology chage. I assume the differences the Whitby, Rothesay and 3 Leander Classes were such that they required substantial design input.. We don't want to end up down the T21 route with no Board Margin for developments. Does a new class entail a new hull design or can it just mean a new weapon and/or sensor fit? The T23s are an exception to having differently hulled batches like T22 and T42 but have an ASW /GP role split. Also we have to include the upgrades to the ships major weapon systems including FW, RW piloted and pilotless aircraft going forward.
Wasn't FFG(X) a five existing design competition with the intention of tailoring to USN needs . Basing on an existing design seems to be the fashion with the USN developing the FREMM and the T31 based on the Iver Huitfeldts which were in turn based on the Abasalon hull. The Arleigh Burke Class in it's various variants will have had a building programme of well over 30 years are they really the same class? The Bay Class LSLs were based on the Dutch Enforcer design. The RAN and RCN are adapting the T26 - if we admit we aren't able to develop aircraft on our own why do we think we can with ships.
(Apologies for the low aviation content in this post)
Agreed the Zumwalts were an ummitigated disaster, IMHO it would have made more sense to test the technologies in existing hull designs before committing. Let's be honest they don't only look like a Monitor that's effectively what they were originally designed for, a role that maybe better suited to air to ground.
The T12-T61 hull was developed at AEW Haslar as the first real post-war hull optimised for NorthLant, but actually only lasted 15 years or so of build. The number of hulls just reflects the size of the fleet at the time. As soon as you had to start mounting guided weapons, or larger ops spaces etc, you ended up with a new design (T82/T42/T22).
The T23 GP/ASW role split is artificial. As designed and programmed, the ships were essentially identical - the difference came when the S2087 retrofit was applied to the youngest eight only.
The T22 and T42 were true batches where additional capability (CESM and later gun for T22) and more Sea Dart for T42 were added to the basic design. Interesting consequence of both stretches was that people forgot that the original hull structure was designed against a bending moment for the shorter hull, which had consequences - most visibly in the B3 T42.
The T45 hull is very different, not as often suggested because of the radar height (it is a factor), but largely because the accommodation standards were vastly improved from the preceding years (6 berth cabins for JRs instead of 30+ messes). That takes space - as does an IFEP plant, all of which means you're better starting anew. T26 had a set of requirements that also required a different hull design (as well as different systems).
The AB are essentially the same design, albeit with some differences at the aft end across Flights I to IIA. But that hull envelope - and the rationale for it - are rooted in the late 80s, which is why some of the things they've had to do for the Flt III are fairly dubious naval architecturally. They're also still using large messdecks, which will hit retention eventually. They would have been better to start anew, but have been frightened by the comedy that was Zumwalt and LCS. Hence also FFGX and to a lesser degree T31e in the UK. Decisions made from a combination of fear and expediency. Interestingly, the RAN are now finding that the changes they want to make to T26 are also having consequences which will be tricky to fix in a fixed hull envelope.
In terms of aircraft (to provide some minor relevance!) I personally think we may have talked ourselves out of the sole design game through a belief that collaboration is the only affordable way to go, possibly as a hangover from TSR2. In an overall programme, including all systems - scratch development probably is beyond national means. But does that hold true for airframe (standfast control system) and propulsion? EAP was done largely by BAe IIRC and while not a warplane as such, was definitely in the ballpark. Dassault are (or were) capable of doing their own thing with Rafale.
Its all about sustaining a design base (something an international programme doesn't do) which actually means aiming for shorter service lives with potentially incremental system upgrades. A cost benefit analysis of that option vs current long-service life (and hence additional costs incurred re-learning) would be an interesting exercise..