By the time the sparks appear, you're already hit. It doesn't take a second or any time for them to hit something. They're actually hitscan. That tactic can sti

By the time the sparks appear, you're already hit. It doesn't take a second or any time for them to hit something. They're actually hitscan. That tactic can still work against them but generally not without a cost to shields, at least not if you take the time to see the sparks. You can use that tactic effectively to deal with other kinds of robots without taking a hit because their projectiles take time to travel. And Descent 2 and 3 had gatling gun robots that IIRC were not quite hitscan, so you could in principle do that with them too. Homing missiles are great against the (visible) vulcan robots but you still need to know where they are, or spend missiles speculatively.