Mongoose Traveler 2 – What is an effect of the critical jet of success?

Consider the following example:

  • Player throws 12 attacks (Lase pistol shot).
  • Then add 2 of his DEX DM and Gun Combat (Energy).
  • Now he's 14, so it's a critical hit because he needed to roll 8+.

But they do not cover that. I only found this fragment.

Damages and effects

The effect of an attack jet is always applied to
the damage of a weapon unless the weapon is destructive or a weapon is
used on a smaller scale target (see page 157).

The player must therefore inflict normal laser gun damage (3D + 3) and add 6.

But in the chapter on vehicles, there is a whole section on critical hits (page 134). It seems that something is missing in Core Book.

Should I just accept that +6 (or more) damage on the critical hit or maybe there is another good mechanic? For example, double the dice or maximize the damage (3D = 18). Or maybe I miss something.