Just me rambling as usual. And NO I am not using Norwegian ship because they are better, I use them as an example, since I know about them more than any "US" ships. So no need for the Norway, Norway, Norway banter. (I am Norwegian, I live in Norway... and we don't care)
as an "interim" it could work, but remember you should put in factors that equipment start to get old and bad.
(Note: these vessel is build for a different climate, that basically mean they are designed to carry more weight on deck, in form of ice. for you'r Mediterranean ships, they would normally notbe designed for accurate that much ice on deck, weight that can go to equipment.)
We could in this case use Oslo class as an example since it's an ship that was in service from 1966 to 2007.
Things you can take from Oslo class:
- speed reduction due to boilers and equipment after and around boilers and turbines are getting old. (Oslo class went from a top speed of 38+- knots down to 25+- knots or lower.)
- guns replaced with something else (Oslo class had it aft 3" replaced with an 40 mm due to the twin 3" was worn out that it could hit a barn from the inside, the other twin 3" was similar condition)
- Weapon upgrade during years (Oslo class got first Penguine, then later AAW missile and new improved radar and systems.
- life boat replaced with a RHIB (Oslo class..)
Another vessel we you could use as an example, is the Danish Peder Skram-class frigates:
Wiki:
As Built
4 5 inch/38 guns (2x2)
4 × 40 mm/L70 Bofors (4 single mounts) guns
8 × Depth Charges
4 × 553mm torpedo tubes (2x2) - Fitted in 1970
After Mid-Life Update
2 5 inch/38 guns (2x2)
4 × 40 mm/L70 Bofors (4 single mounts) guns
4 × 21 inch torpedo tubes (2x2)
8 - Harpoon SSM
1 × 8 Sea Sparrow SAM launcher
8 × Depth Charges