the effect appears to be a simply trail effect.
essentially, as you move along, you record several points(position, and direction of thruster, and a time to live for that point).
you generate a series of rectangles starting at the source thruster, and create a rectangle between the current point and the next point(using perpendicular direction from each points's recored rotation).
basically this diagram well hopefully explain it well enough:

to see the above method in action:
http://www.youtube.com/watch?v=W0PEXdCuwAM&list=UU20WP2UmRxhYDAsyun8KGBQ&index=1&feature=plcp
their are other ways(such as re-drawing the previous frame, but fading it out a bit, then draw the current frame).
Edited by slicer4ever, 06 February 2013 - 07:46 PM.