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On the way home from Kazakhstan, I went through Moscow. At Sheremyetyovo, an hour after the departure time, Aeroflot finally explained there is a mechanical problem with the 767 - they are looking for another plane.
I watched them hook the 767 up to a tow truck and pull the plane out to the fence line.
After another hour and a half, they announced they found a 767 - inbound from Sophia Bulgaria that is not scheduled for another flight and could be our replacement airplane.
Meanwhile, the original 767 sat out at the fenceline. Unattended.
After 5 hours, Aeroflot announced that the original 767 is OK for service and pushed the plane back to the gate.
Apparently, all that was wrong was: "the windshields were dirty".
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