To be successful getting this you will need to spend starts at the hangar, leveling up the shield power up. you need to stay crushing a wave of enemy planes so at least half bar should be upgraded,
once you are ready pick any level where you are familiar with it, and when a wave of planes comes up the screen, line it up where all will be passing through and press the [ ] (square) button. If you manage to keep the shield active between the first and last plane from the wave, you will be awarded with the achievement.
It is a lot easier to do if the wave of enemies are going in a straight line, upper vertical to lower vertical, instead of doing circles or some strange figures like many waves of enemies. Anyway, any of them can be used.