Things that go "BOOM" (in the daytime)

My first job out of college was working for the Power Company in Southwest Virginia.  I was assigned to the Communications Group that maintained the company's carrier relay, microwave, telephone, base and mobile radio systems.  Mainly, it was office work, but I got to go out with the Field Service Crew from time to time.
 
One day, we were called out to service the supervisory phone circuit at the Smith Mountain Hydroelectric Plant.  Since we suspected a bad channel unit in the FDM microwave radio system, my buddy went behind the rack to chase the cables, and I went in front of the rack to pull the suspected channel unit.  
 
Initially, the channel units had been labeled with DYMO labels, but they often fell off in a dusty, moist environment.  My buddy got out the "sheet music" (the signal path schematic) -- so called because it reads from left to right with a bunch of lines indicating signals (looks somewhat like a music staff) and the dots on the lines indicating terminations.  Reading the sheet music, he called out to me "The fifth channel."  I said, "From the right or the left?"  He said, "Right, NO, LEFT!!!"  He made a common mistake, he transposed right to left, TWICE!!!  From down the hill at the Hydro Plant, there was a resounding KABOOM!!!
 
Anyone who has heard air breakers actuate, knows the sound.  Normally, if a 138 kV breaker opens in air, it would just draw an arc and the ionized air would STILL conduct electricity.  To prevent this, the arc is blasted away with jets of air at 1200 PSI, hence the loud noise.  The maintenance phone on the wall started ringing and my buddy advised me not to answer it.
 
When I got back to the office, my reputation as "Sparky" had preceded me...and less than ONE YEAR into my engineering career!!!  After all, how many people had ever single-handedly tripped a power plant offline???

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