CLE-DTW
I noticed looking at the new schedule Delta has reduced CLE-DTW to 4 roundtrips a day. Their used to be 6-7 a few years back. They are all RJ's to.
NW used to fly alot of DC9's and even Airbuses on the route.
I fly CO most of the time but when CO was Skyteam I would be routed on NW and DL flights. From observation, the CLE-DTW flights look packed all the time. Alot of people making connections. CO dropped CLE-DTW a few years back so I hope they may reinstate the service. 4 flights a day to a large hub is not really enough.