At the time they were calling these planes "Yellowbird" and used a song about a yellowbird in their commercials. The plane I flew on was a DC-9 like the one pictured. They also used DC-6's to fly in and out of Bangor. After flying from Bangor to Boston, I flew to Chicago on one of the major airlines, which I don't remember which one anymore. I do remember I was flying stand-by and as a result got to fly this leg First Class as those were the only seats left when it was my turn to board. Had my first Vodka Martini and enjoyed it, especially when drinks in First Class were free!!
From Chicago to UP on the tundra, I flew on North Central Airlines. They liked to call themselves the Blue Goose, but some who worked for them and some of us passengers called it the Ruptured Duck!! This plane is a Convair 580, which is the type of plane that I flew on this trip. Eventually all of their fleet was DC-9's before becoming Republic Airlines when they merged with Southern Airlines. Later they bought Hughes Air West which also had DC-9's. The Hughes Air West planes were solid yellow and after Republic bought them, they did an ad saying they were peeling the top banana in which they peeled off the yellow Hughes Air West colors to reveal the Republic colors underneath. (This was about 15 years after my trip.)