How to know the horizontal distance between remote controller and aircraft?

There is no method to directly get the horizontal distance between remote controller and aircraft, you need to calculate by yourself. Since you know the co-ordinate of remote controller and aircraft, you can use Pythagorean theorem to calculate the horizontal distance.

The method of getting co-ordinate of remote controller:

• setGPSDataCallback, Only the the remote controller that supports LB can call this method.
• Currently lots of aircraft does not support the above method. Since the remote controller or the connected Android device can connect to the internet. You can use internet to get its location.