Would an Iron duke be such as bad idea ?
It would not fit with the defensive plan but it would act as a massive threat to any German/Russian invasion fleet.
What ships could stand up to fighting a 8x13.5 BB (with a bit of deck protection modification + increased elevation main guns ?) would S&G be it I think and would they be risked ?
JSB
Easy, give me two Bjorgvin class CDS with it's standard escort of up to three torpedo boats and the Norwegian coast line. What would happens is:
- torpedo boats is hiding under camouflaged behind some small islands/rocks. both the CDS will go out in open sea and open an over the horizon't fire, well outsinde those 13.5" guns range.
(Bjorgvin class 9.2" guns have a standard range of 27 km, 39 km supercharged. 13.5" guns maximum range is 24km)
- then the CDS will pull back, but at the same time keep the BB interested, and since the CDS is small, they are difficult to hit. (small target).
- when they get inside one of the fjords, they will start to use the surrounding mountains as armor, and open fire only when they are poking out from that spot, but at the same time changing position.
- the BB moves in, so she can get those CDS. but that just give the CDS an better angle to fire there APC/HE ammunition, and more easy place every shoot. (easier to place shells from a smaller guns)
- and when the BB is inside the fjords, she would be torpedoed from three different direction by those damn torpedo boats, and while the BB is licking here wound the two CDS will come out, and give an close range firing with its fast shooting 6", destroying up anything on deck, while here 9.2" is focus firing the turret rings and sighting mechanism on the BB, take here main guns out of action. bit here comes the nasty surprise, those two CDS sends away a couple torpedoes in here... just to make a point.
all this is without taking in to account of all shore battery's.
you should be glad that i don't mention those much older CDS Norway had, yes they had there weakness, but they had an party trick up there sleeve. those old 8.3/8.26" guns Norway used was modified to do one special things, and that is to lob a shell over an mountain, howitzer style. And in that time period of those 13" guns you are talking about, Norway had 4. CDS with 8.3/8.26" guns, totally 8 guns that can lob shell over the mountain. while the Bjorgvin class 9.2 need an more direct angle.
This is an tactic Norway used many times in the olden days to great success. lure the enemy in, great hell, ..play with the food, finish it off with style.