At the cavernous lab of Lightning Technologies, in Pittsfield, Mass., you first hear a horn’s warning blast, then a huge kapow. That’s the sound that electrons make when 2.4 million volts send them burning a zigzag path through the air. The bolt proceeds from the hanging double corona ring to a model supplied by one of the lab’s clients, in this case an airline that needs to test how lightning affects its planes’ ever more pervasive electronic control systems. (If you’re a frequent flier, you’ve surely been zinged by Zeus several times already.)
The blue tower consists of a stack of capacitors separated by spark gaps. It takes five or 10 minutes to charge all the capacitors, but when they’re ready, a single spark jumping a single gap is all it takes to start the avalanche of electrons.
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