Parent OffSet?

Hi BlenderArtists, i have a turret sentry gun which, when it shoots, will show a flash image.
obviously it needs to be parented to the gun, so when it rotates, the plane stays in the same position relative to the gun. at the moment, it only shows the plane, to align first. But when i play the game, the planes are moved all over the place.
if doesn’t work check :

I haven’t checked your file. Such things usually happen, when one or more of the parents are scaled in object mode.
Apply scale <ctrl>+<A> to all parents should help.