[Zanthis]

To answer your question tbontob, understand that components (which includes armor) are either totally destroyed or uninjuried. As a result, every ship tracks "unassigned damage" which is the extra damage that has not yet been used to destroy a component.

Suppose you somehow built a ship with only two pieces of Armor III. It takes 45 damage. Since it requires 40 damage to completely destroy a component, one of your Armor III components will be destroyed. That leaves 5 damage, and since the only remaining component takes 40 damage to destroy, that 5 damage becomes "unassigned". The next time that ship gets hit, that unassigned damage gets added to the new damage to try and destroy more components. So another hit for 35 damage will kill the second Armor III component since 35 new damage plus 5 previously unassigned damage equals the 40 damage needed to kill a piece of Armor III.

Got that so far? Ok, the game appears to try and never leave too much unassigned damage on a ship. As a result, the game builds a list of all components that can be destroyed given the current amount of new damage plus unassigned damage and picks one at random to destroy. It repeats this process until the list is empty.

Consider you had Armor I, Armor II and Armor III on a ship. Two of each. They take 20 damage, 30 damage and 40 damage to kill respectively. Visually, they could be written out like this:
> 20, 20, 30, 30, 40, 40
Now suppose this ship gets hit for 10 damage. The game builds a list of all components that can be killed with 10 damage. If such a list is in []'s, it would look like this when combined with the above list of armors:
> [] 20, 20, 30, 30, 40, 40
Nothing in the list, so nothing gets destroyed and the 10 damage becomes unassigned. Now the ship gets hit for 15 more damage. A list is built of all components that can be killed with 25 damage (the 15 from this hit plus the 10 unassigned from Last hit). This list looks like:
> [20, 20,] 30, 30, 40, 40
So one of the two Armor I components will be destroyed. That will leave 5 extra damage, for which a new list will be built. That list will obviously be empty and so that 5 extra damage gets kept as unassigned damage on the ship.

Lets reset our ship to undamage, and consider what happens when it gets pounded on by a 30 damage weapon repeatedly. Each single hit is one line. I'm listing weapon damage on the left before the '>' sign and previously unassigned damage there too, after the '+' sign. So "30+5>" means hit for 30 and there was already 5 unassigned damage on the ship.
30+0> [ 20, 20, 30, 30,] 40, 40
30+0> [ 20, 20, **, 30,] 40, 40
30+10> [ **, 20, **, 30, 40, 40 ]
30+0> [ **, 20, **, 30, **, 40 ]
30+10> [ **, **, **, 30, **, 40 ]
30+10> [ **, **, **, **, **, 40 ]
0>
Now lets do 11 damage per hit:
11+0> [] 20, 20, 30, 30, 40, 40
11+11> [ 20, 20,] 30, 30, 40, 40
11+2> [] **, 20, 30, 30, 40, 40
11+13> [ **, 20,] 30, 30, 40, 40
11+4> [] **, **, 30, 30, 40, 40
11+15> [] **, **, 30, 30, 40, 40
11+26> [ **, **, 30, 30,] 40, 40
11+7> [] **, **, **, 30, 40, 40
11+18> [] **, **, **, 30, 40, 40
11+29> [ **, **, **, 30, 40, 40 ]
Ok, I stopped there, but notice how the Armor III is now a valid target? That is because using the formula: E + 2R - A + 1, 11 is the minimum damage value needed if you want a chance to kill Armor III before destroying all the Armor II. Effectively, E should be the damage to kill the component you want to kill (40 in this case), and A should be the damage to kill the component you don't want to kill (30 in this case). Since their is no emissive armor in this example, R is zero.

I hope that cleared it up a little. I'm still running tests, especially since there has been indication in this thread that internal damage assignment may vary from armor damage assignment.