[Marty Ward]

There are two different movement abilities you can assign to a hull, standard and combat. If you assign standard movement you it's like having additional engines. If you assign combat movement it like having afterburners for ships.
Check out the Abilities file to get the exact wording for the abilities. If you add abilities remember to change the number of abilities line in the hull.
You can mix and match as you like, ie escorts get 2 extra standard moves and 3 extra combat moves and destroyers get only 1 extra combat move etc.