As a passenger, if I'd heard a loud bang coming from the cockpit followed by a glowing ball of gas rolling down the length of the aircraft, I'd be recommending the pilots go see a dietitian as soon as possible. I'd also be holding my breath.
Clearly the regular airline food has done a lot of damage to digestive systems.
My question is; how is it possible for such a phenomenon (one would assume of an electrical nature) to penetrate a Faraday cage?
No Faraday cage is perfect, especially when it comes to RF. Screened rooms (the kind of place where one does a lot of RF testing and equipment development) have to be "tuned". They're actually double skinned, one Faraday cage inside another, with the gap in between being chosen to make the screening good over a specific frequency range.