China conducts test flight of a giant coil array. Can it detect nuclear submarines?

China has successfully tested a novel airborne electromagnetic detection system, potentially capable of locating nuclear submarines. The system, called Airborne Transient Electromagnetic (Atem) detection, involves a helicopter towing a large coil array. It works by emitting a powerful electromagnetic pulse that penetrates the ground or water, inducing eddy currents in conductive materials. A receiver coil then detects the secondary magnetic field generated by these currents, allowing scientists to analyze the object's presence, depth, and composition. The results of this test flight were published in the Chinese journal Acta Aeronautica et Astronautica Sinica. Associate professor Fu Jingcheng of Beihang University and the Chinese Academy of Sciences' Institute of Geology and Geophysics led the research, overcoming significant engineering hurdles to stabilize the complex multi-coil system during flight for geophysical surveys.