On behalf of Midway Airlines and its 4,700 employees nationwide, I sincerely appreciate the vote of confidence afforded by the editorial "An Idea That Will Fly," Aug 12.As you know, Midway Airlines' size and scope afford it the opportunity to be immediately responsive to what we see as a logical approach to the general consumer. Over the past 12 years of its history, Midway Airlines has prided itself on being "user-friendly." This latest step - making its tickets refundable - is yet another tactic in our overall strategy. The Monitor is one of the United States' most respected publications and we appreciate its support. Sandra Allen, Chicago, Communications Director, Midway Airlines Letters are welcome. Only a selection can be published, subject to condensation, and none acknowledged. Please address them to "Readers Write," One Norway St., Boston, MA 02115.