Special thanks to Bubblehead1980 and his new release here:
Linky
We have both found out that the stock / FOTRSU / and his own model had no A0X nodes within the DAT.file, so was defenseless against all air attacks.
Stock / FOTRSU / HakodateFrigate Mod
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with added A01 & A02 nodes, adds Two "20mm_Double_base_US Guns" on main gun platform
Now included in - FOTRSU Fxies v0.64x @ Area 51 in Core Assembly