If a crit goes off agaist a ship with no shields left does it count as 3 hits of damage?

If a crit goes off agaist a ship with no shields left does it count as 3 hits of damage?

What do you mean by "a crit going off?"

Let's say you roll the dice and after the defender spends defense tokens all you have is one black die with a crit+dmg face showing. You then get to the Resolve Damage step:

First step is to resolve one critical effect. You choose to use Concussion Missiles. Each arc adjacent to the one you're attacking takes one damage. If neither of those arcs have shields, the defender would then draw two face down damage cards.

Next the defender suffers damage equal to the number of damage and crit icons showing. There are two, so the defending arc suffers 2 damage. If that arc has no shields, the defender would draw two more face down damage cards.

if you are referring to the black die critical, and you are saying you hit the front hull with 1 black die critical ONLY all the other dies show no hits, then yes the front hull would suffer 1 hit, then because you have the concussion missiles card, each left and right hull would suffer hit/damage for total of 3, and since no shield they would all go against the hull.

Hence why Concussion Missiles are so scary. Hell, hence why all ordnance upgrades are so scary, really.