Double-decker passenger planes are a dying breed. These airlines are keeping them alive

CNN
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They’re massive pieces of engineering that seem to defy physics as they hang in the air during takeoff and landing, but double-decker passenger airplanes — the Boeing 747 and Airbus A380 — are still some of the most popular aircraft around.

Perhaps it’s their whisper-quiet cabins and spacious designs. Or the availability of opulent amenities, like shower suites and onboard bars. For…