Timmymagic wrote:If you had a choice a 76mm at c£3m per unit or 57mm gun at c£5m per unit OR a free 4.5 inch main gun plus something else?
Depends.
If it is Leander, 76/57 mm do not require re-design of forward section, which will make it cheap. Also the arsenal will be very small, and will not carry many shells. If Arrowhead 140 or MEKO A200, no re-design is needed, but not sure about how many shells they carry. So, Leander pushing for 57/76mm is reasonable (not saying 4.5inch is bad).
The 4.5 inch is large, heavy and shall require much more maintenance than 76/57 mm = costy to operate. On the other hand, even though 76/57mm can share logistics and investments with NATO navies, it is new to RN, as you said. Which will win?
Personally for T31 4.5 inch makes perfect sense. It will actually deliver a decent volume of fire ashore with decent sized shells, can deliver a large airburst round if necessary against a UAV, USV or FIAC and can actually stop a decent sized ship.
I read somewhere that airburts round has been decommissioned?
And anyway, here is the key points.
- Without guided round, 4.5 inch NGFS will be very limited compared to modern 5inch guns. I suspect even 76mm Volcano guided round is better in NGFS than non-guided 4.5 inch round (I might be wrong). I am also sure a guided-NGFS-round for NGFS for 57mm will emerge soon (maybe a modified ORCA).
- STARES/DARTS round for 76mm, and 3P and Orca rounds for 57mm is much powerful than simple 4.5inch round. In other words, in AAW and close-in defense, 76/57 mm is much better. As I understand, 4.5 inch is now almost nothing in AAW.
But, I shall say, Volcano or STARES/DARTS for 76mm is expensive, and will not be included in T31e as built. Comparing "normal" 57/76mm vs 4.5 inch, latter is surely much much better in NGFS. But, not in AAW (note 57mm is by default with 3P). These "options" make the cost and effect comparison a bit nasty...
In a budget constrained world my only preference ahead of it would be if we could find some US 5 inch mounts going cheap that could be re-furbed. At least it might have some commonality with T26 then, but then again T45 would have an orphan calibre for the remainder of its life...
Agreed. No guided round is needed as built, just a 5inch gun, with common mechanics will make it a winner. Simple 5inch gun has all the deficiencies I listed up the 4.5 inch gun has. But, it has a bright future with significant investment on-going, while 4.5inch is a dead-end. I also think 5inch gun is requires less maintenance/manpower than 4.5inch? At least, it is more compact.
I even think, leaving 2 T31e with 20mm CIWS on A-position (without mid-cal. gun), and buying three 5inch gun for the other 3 T31e could be and interesting option.