US could turn LGA into a profit center if they would just use their mainline aircraft instead of flying all these express flights. I know UA flies LGA to ORD. US could do LGA to MDW. LGA to PBI. I am just pulling some cities out of my head that seem that they could possibly do well. I know so many folks that are from NY that live in PBI alone.
I think the F/A's have a clause in their contract that prohibits LGA-PBI. (Just kidding.) This city pair was operated for some time, and I think it did very well, but the F/A's thought this was the ultimate horror story as regards the passenger makeup. Rumor has it that three new-hire reserve F/A's flew their first LGA-PBI segment and all three quit on landing in PBI.
US used to do LGA-MSY, and the flights were always packed (I know, not necessarily profitable.) Then Katrina hit, and MSY closed for a while. US was the last carrier to resume service at MSY when the airport reopened. And the LGA-MSY route never reappeared.
US also ran LGA-BDA which WAS profitable (according to the company.) Then another hurricane shut down BDA for a while, and the company promised that once BDA could handle the flights, they would resume the service. This was at least four or fie years ago. Still no LGA-BDA.
And they ran LGA-NAS seasonally. It appeared successful. That left one spring, never to return.
I was told that there is no such thing as rj vs mainline slots. At LGA, a slot is a slot. It is up to the airline whether they assign an rj or a full-size a/c to the slot.
I'm not certain, but I think the only exception to that are 757 and heavier aircraft. When these are used, the arrival and departure rate is necessarily slowed due to wake turbulence restrictions, so I think the PANYNJ treats these slots differently.