I see in editor, that class 152 'T' War Emergency indeed have ZERO as Oerlikon ammo - so obvious DB error. Class 153, which is upgrade to 152, have ammo at 18. This is in Scenario 1, in Scenario 2 there is no split tubes, and Oerlikon have right ammo, so error probably was implemented during changing of tubes.
ORIGINAL: Iron Duke
the OP looks to be using a MOD - possibly one of the dababes variants - as they have the torp tubes broken down that way , i don't think the official scens were changed so they show a large block of fwd firing torp tubes as per post 2 .
Split tubes were introduced in Babes, but it become official in one of the patches, and ALL submarines should have them in batches of TWO. If there is SIX tubes in one slot - this is error.