Back in March, we noted that Salt Lake City (SLC) was the biggest market without at least seasonal nonstop flights from Charlotte. Well, that is about to change. Come March 4, 2012, US Airways will offer a daily flight to Salt Lake City. The flight leaves Charlotte at 8:30pm and gets into Salt Lake City at 10:45pm. The return flight is a red-eye, leaving SLC a minute before midnight and getting into the CLT just before 6 am. The service is on a 150-seat Airbus A320 and is expected to operate year-round.

Salt Lake City is, of course, a Delta hub. In 2007 and 2008, Delta flew CLT-SLC but rising fuel prices caused the airline to drop the flight. There’s a significant difference between Delta’s former service and what US Airways plans to do though: Delta’s flight left Charlotte in the morning and the flight from Salt Lake City got back into CLT in the evening. Which is to say, the opportunity cost of offering the service was much higher — Delta was tying up a plane for most of the day to offer the flight — while US Airways’ red-eye service involves using a plane that would pretty much just be sitting on the ground somewhere overnight.

Bonus observation: The last time US Airways added a domestic destination from Charlotte was Baton Rouge in June 2010.