Back in the 1940s, two first-time flyers took a plane from New York to Los Angeles. When they made their first stop – at Philadelphia – a red truck arrived to put fuel in the plane. A little while later, they landed in Pittsburgh, and again a red truck pulled up to fill the plane's tanks with fuel. Each time they landed to discharge or take on passengers, a red truck would pull up and add fuel to the tanks. Finally, after landing in Kansas City and seeing the truck pull up again, one passenger s…