NASA/KSC Launch Pad Lightning Warning System

Thunderstorm Technology

Electric Field Mill Sensor in inverted tripod mount.

The Advanced Ground-Based Electric Field Mill (AGBFM) sensor is part of a suite of instrumentation used by the 45th Weather Squadron at Patrick Air Force Base to assure safe missile launch operations. The AGBFM sensor detects the build-up of electrical charge in clouds by measuring the lines of electric force that emanate from a cloud and terminate at the earth's surface. The downward orientation allows reliable measurements to be made during the heavy rain that usually accompanies storms.

To provide coverage of the extensive launch facilities, the AGBFM Sensors are located around Merritt Island.

The Air Force and NASA have developed a set of launch commit criteria that rely on Electric Field Mills to ensure that hazardous cloud conditions are avoided.

AGBFM Sensor Specifications:

• Continuous operation in a marine environment;
• +/-32 Kilovolt/meter full scale;
• 4 Volt/meter resolution (14 bits);
• 10Hz bandwidth, 50 samples/second;
• Digital serial packet communications.