This is a classic commercial for Republic Airlines. I chose it not only for the retro Boeing 727 and DC-9, but for sharing the idea of positive letters. Believe it or not, airlines actually do receive letters like this and I have been to more than one airline headquarters where they proudly display them on the wall, to remind workers that some folks are appreciative. For most airlines, all letters (good or bad) are read.
The Republic Airlines in this video is not the same today that operates Frontier. In 1986 Republic Airlines was purchased by Northwest Airlines, which is now part of Delta.