I lost my spark recently when it flew off course during a Litchi way point mission. After reviewing my flight record Litchi responded "...GPS signal was lost, generally this is because of strong interference". The flight record indicated 18-20 satellites up to the point of losing communication well after it left the mission. This was in rather remote mountainous area. (Homes in the area are on 10 acre parcels many of which are unoccupied.) I'm trying to figure what possible source of RF interference could have caused this.