Because Stormscope weather mapping systems detect electrical discharge activity, antenna placement relative to other active electrical components is critical. The antenna must be placed at a location that is free from excessive electrical interference. The ideal location varies for aircraft to aircraft. To ensure an interference-free antenna location, every aircraft must be skinmapped prior to installation of the Stormscope antenna. The skinmap must be done with the engines and all electrical systems operating. The Stormscope requirement for an antenna ground plane and a noise free environment complicates installation in aircraft with wood, fabric, or composite construction. Each aircraft needs to be analyzed individually for best antenna location. Avoid mounting the antenna near active electrical components whenever possible. General clearance guidelines are: - Strobe lamps and power supplies 5 ft. (1.5 meters) - Pitch trim servos and amplifiers 3 ft. (1 meter) - Fluorescent lamps and ballasts 5 ft. (1.5 meters) - Heater ignitors 5 ft (1.5 meters) - Air conditioner and heater blowers - DME/Transponder/TCAS antennas 4 ft. minimum (1.2 meters) - Inflight telephone antennas 4 ft (1.2 meters) - VHF comm antennas 1 ft. (.3 meters) - ADF antennas 1 ft. (.3 meters) - Any current carrying cable 2 ft. (0.6 meters) Stormscope sensors are adversely affected by the build up of static charges. Do not mount the antenna near any composite materials (e.g. plastic covers, radomes, fiberglass housings, windows, etc.) as these devices can build up static charges. Avoid mounting the antenna in the ground return current path between the battery and alternator, and the battery and blower motors of other heavy current carrying equipment. Aircraft skin currents may cause antenna interference.