The GQ3 rules are good, I will not deny that but I think they have been over simplified in some regards. It strikes me as strange that the in service dates of some equipment is tracked down to the month in which it was introduced but in other regards, the rules are are very simple in their modeling of WW2 naval combat. Belt and deck armour is represented by a single factor but turrets have their own values.
The armour classes given for each class are a combination of deck armour, belt armour and general vulnerability to damage of the ship. Yet it fails to take into account that the deck armour and belt armour of a certain class might not give the same 'value' of vulnerability.
For instance, the modern battleships of WW2 had thick deck armour to resist plunging shells and bombs which were far more common in WW2 than WW1. WW1 battleships have thick belt armour but thin deck armour because the ranges were shorter and so the flight path of the shells are flatter. However under the present rules either the WW1 ships get a bonus because of the thickness if the belt or are penalised because of the thinness of the deck compared to WW2 ships.
So what to about it?
On the range charts, there is a line showing whether the shooting is high angle (and so pass over intervening ships) or low angle. This also indicates whether the deck or belt is hit. If all armoured ships have 2 armour factors, 1 for belt and the 2nd for deck, using the same classifications as now, i.e. BB, CA etc, then the difference between WW1 and WW2 ships can be more accurately modelled. For instance the Hood would have a rating of BB/BC. That is BB for the belt and BC for the deck.
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Using the range charts, depending on the gun and range, a shell would either hit the belt (underneath the line) or the deck (above the line. Whether or not the shell penetrates still depends upon the penetration power of the shell vs the armour of the ship where the shell hits. There is no need for complicated rules, just the one stating whether the belt or the deck is hit.
Of course, the deck armour value would have to be worked out for each ship.
The rule: "when a hit is registered, the range chart is consulted to determine the whether the belt or deck armour of the target ship is hit. If the range is above the line then the deck is hit. If the range is below the line then the belt is hit. Only the range from shooter to target is taken into account. No range modifiers are taken into account. Once the armour of the target is determined, then the penetration value of the shell is compared. Then damage is worked out as per normal."
So what do people think?