Prop, thank you. There are some variations of the SE5a but these were, for the most part, field modifications and not standard factory produced air craft. When the SE5 was first introduced into combat some pilots, used to flying the Newports, took the dihedral out of the wings. The standard plane has 5 degrees dihedral and they reduced it to 2-3 degrees. This made the plane less stable The down side to that was that the it also made a less stable gun platform. So.. once they got that sorted out they left it alone.