The official party line is as follows (if anyone has a more recent quote, please chime in!)
Thought I would pop in a clarify a couple of things. There are a couple of ways to break a lock-on sequence when no missile has been fired yet:
- Skilled piloting, such as maneuvering outside of the opponent's secondary firing arc, or trying to break line of sight by zooming around or inside of asteroids or other objects.
- Activating a defensive maneuver type engine ability (such as Koiogran Turn, Power Dive, Barrel Roll, Retro Thrusters or Snap Turn).
Once a missile is in-flight, the only way to avoid being hit is to activate a defensive maneuver type engine ability (the same list as above). This will 'evade' the missile. Visually, the missile will still complete its journey towards your ship, but it will not explode and no damage will be done to you.
As an added bonus, when your ship is actively executing a defensive maneuver, enemies cannot lock-on to you. On their end they will hear an error buzz when they attempt to right click to lock-on.
Hopefully this clarifies a few things!
Found here: http://www.swtor.com/community/showt...=705142&page=2
All that being said, there is also a slight delay between your PC and the server, so sometimes it may appear to you that you engaged a missile breaking ability before the missile has impacted, when in fact the server has already registered the hit. This is pretty unavoidable, so my best advice is don't wait quote as long to Barrel Roll