Wide and narrow bodies are, at some times during the day, used between all of United's hubs. From IAD, you have a better chance of getting a 777 if you were to fly to LAX or Denver. I don't recall any domestic flights with 747s at IAD this year....just the one each to Frankfurt and London.
, widebodies are usually scheduled to coincide with the heavy late afternoon bank of flghts from and to Europe. This is to meet the demand of passengers flying from Chicago through IAD
and those from Europe flying on to Chicago. Some of the widebodies coming in to IAD
from domestic hubs usually fly onward to one of United's European (or later in the evening to South America). And some of the inbound aircraft from Europe turn and fly on to United's domestic hubs. During lower demand times, you'll see something as small as a 737 flying between Chicago and Dulles and between other hubs.
[Edited 2004-12-13 13:53:10]
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