After the merger of CO with UAL, CLE served as an East-West and to some degree a Midwest-South hub for travel between smaller markets. With CLE gone as a UAL hub, old traffic that had gone through CLE (typically smaller town to smaller town travel) now has to go through EWR, IAD or ORD. My guess is that the extra seat capacity into EWR, IAD and ORD is not just filling more seats on existing planes, or moving from RJs to larger aircraft, but by adding actual take offs and landings. However, I do not know this to be true. Does anyone know if UAL has increased the number of flights into these hubs? Is there no end to how much traffic these hubs are allowed to handle? Is there any evidence that the loss of MEM, STL, PIT, CLE and CVG created worsening congestion and flight delays?
United cannot add flights at EWR due to slot restrictions.
United added a few flights to ORD, (moving former CLE flights to FNT and ERI to ORD) and beefed up the CLE-ORD schedule a little bit. But other than that they have not added flights.
IAD has not seen any additional flights. However, IAD is also not anywhere near its capacity, so if they did, it wouldn’t cause any congestion.
There’s no hard evidence that any other hub elimination has caused increased congestion elsewhere. Usually the only flights that are added at other hubs when a hub is cut are flights to places that were only served from the soon-to-be discontinued hub.