The Southwest Airlines web site http://www.southwest.com/html/customer-service/baggage/carryon-bags-pol.html
gives a maximum size for carry-on items of 10 x 16 x 24 inches, which is smaller than my lute case. I wonder whether they enforce this strictly. >From talking with other people, I have this set of rules: 1. Use Southwest Airlines if possible. 2. Fly early in the day to maximize your chance of getting an overhead bin in the cabin. 3. Have a lute case that fits in the overhead bins. To get on or off this list see list information at http://www.cs.dartmouth.edu/~wbc/lute-admin/index.html