The electrical bonding of the antenna to the aircraft ground is extremely important. If this is not done properly, antenna performance characteristics may become distorted and nulls may appear in the antenna radiation pattern. This, in turn, may cause erratic navigational readings or signal drop out.
The electrical bonding of antennas to composite aircraft is best accomplished by direct metal-to-metal contact of the antenna mounting hardware to an internal ground plane. The GPS antenna can be installed either inside or outside the vehicle.
It should be placed horizontally for best GPS reception. The GPS antenna must have a clear view of the sky. If you install the antenna inside the vehicle, place it close to a window; GPS signals can pass through glass but not through metal.