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Join Date: Sep 2009
Location: Minneapolis: DL DM charter 2.3MM
Programs: A3*Gold, SPG Plat, HyattDiamond, MarriottPP, LHW exAccess, ICI, Raffles Amb, NW PE MM, TWA Gold MM
Posts: 100,399
In the past, DL did their own de-icing at MSP and ATL at least. I suspect the same is true in DTW and other hubs, with airports doing it at smaller airports or places where an airline doesn't have significant operations (although ground handlers could also do it at some airports).