I'm not familiar with the P4, but the landing gear is probably similar to previous models. Here's where I have it mounted on my P2V+. I chose this location based on a conversation with the manufacturer. Best signal strength received will be from a vertical antenna, worst will be from a horizontal one, and somewhere in between from an antenna at 45 degrees. So in thinking about how it might land after either an auto-land or a fall, it seems orienting the antenna along a landing leg will have it wind up either vertical at best and 45 degrees at worst. It cannot wind up horizontal to the ground in this position -- unless it gets hung up in a bush or tree. I'm just playing the odds here for the strongest signal possible. I attached it with a piece of Velcro.