No, Delta deicing in Atlanta is not contracted out. It is done by Delta ramp, as in all other Delta cities where the ramp is staffed with Delta or Delta Global Services employees.
The problem is that Delta only has something like 10 deicing trucks in ATL. They are ill equipped to handle the kind of weather that they got, and can you blame them? It's Atlanta, not Chicago or Detroit. In comparison, we have four Delta deicing trucks here at PDX and we only have like 20 mainline flights a day.
I don't think ATL vs DTW is a fair comparison since NW should have been prepared to take care of the irregular operations for a hub that is used to seeing snowy winters.
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