What and where are "flotation seat cushions"?
It became something of a meme:


  In the unlikely event of a water landing, your seat cushion can be used as a flotation device.


You remove your seat cushion and hold the straps on the back as a flotation device. It's probably more of an aircraft/airline thing than by country. It seems that the industry is favoring life vests more, as they are designed to keep a person afloat and face up even if unconscious and not adding the requirements to the cushion allows the seat to be smaller and lighter.



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