In 30+ years of flying I've never come across one of these mysterious 'air pockets'. This must have been one!
Well in French they are called " trous d'air " or " air holes" and yes , they do exist, but you only noticed them if you are a pax
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back to the thread : dropping 7500ft and climbing again to original altitude ? From an ATC point of view this does not make sense if it was caused by severe turbulence. .Maybe a camera stuck somewhere again ?