Simmons, Metroflight, Command Airways, Wings West,....Chapperall, Air Virginia, Avair (and I am sure one or two more) ....all existed in the late 70s and early 80s... Command Airways goes back to the mid 60's...... historical note.. all of these companies eventually ended up under either the Simmons certificate or the Flagship Airlines certificate owned by AMR and flying as American Eagle... and were latter all folded into the "American Eagle" name using the old Simmons certificate.