Sandstorm in Dubai caused panic on QA plane

Luckily nobody was hurt but it must have been a terrible experience . Who would have thought that something goes wrong on a routine flight like Doha Dubai ? Unfortunately , a huge sandstorm made the plane lose altitude -so sharply that the passengers were sure for some moments that the plane was to hit the ground .
The QR 112 from Doha ' pilot lifted back the plane to normal altitude and returned to Doha .

I am not an aviation expert and I would like to understand how and why all this happened .Why the poor visibility the brownout made the plane lose altitude ? Aren't there sophisticated devices built -in the plane to avoid such incidents ?


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