
Sixty Million Car Bombs: Inside Takata’s Air Bag Crisis (2016) - camtarn
https://www.bloomberg.com/news/features/2016-06-02/sixty-million-car-bombs-inside-takata-s-air-bag-crisis
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camtarn
Just got my Honda airbag replaced about a month ago. The letter sounded
alarming enough - "airbag overinflation leading to pieces of the metal
inflator being propelled into the cabin area" \- but I hadn't realized quite
how big the bits of shrapnel were, and I didn't know why it was happening.

"Ammonium nitrate has five phases of varying density that make it hard to keep
stable over time. A propellant made with ammonium nitrate would swell and
shrink with temperature changes, and eventually the tablet would break down
into powder. Water and humidity would speed the process. Powder burns more
quickly than a tablet, so an air bag whose propellant had crumbled would be
likely to deploy too aggressively. The controlled explosion would be just an
explosion."

