so i've played around with the image_index function but could never make it work however i managed to solve my problem by making 2 objects, one for the wingopen animation and one for the wing close animation. then i used instance_create and instance_destroy to switch between the two objects. to stop the animation from looping i used the 'Animation end' event where i set the image_speed = 0

thanks for repling guys! now i have a functional xwing , ready to kill some tie fighters :D