Boeing 747 made intercontinental flights a possibility, thanks to its huge size. Especially trans-pacific flights. Before the 747 you had to do many stops along

Boeing 747 made intercontinental flights a possibility, thanks to its huge size. Especially trans-pacific flights. Before the 747 you had to do many stops along the way, the 747 brought direct flights. It was truly a game changer, anything that came after was just improvements. There were no direct New-York - Tokyo flights before the 747. And that's not happening on a 737 any time soon. This is due to simple laws of physics, really: fuel consumption grows with the exposed surface of the plane (roughly growing with the square of its size), while the size of the fuel tanks grows according to the volume (roughly the cube of the plane size). Hence small planes for short trips, big planes for long trips, and very big planes for very long trips. Of course advances in efficiency allows for smaller planes to go further, hence why the A380 failed, the 777X is failing, and even the A350-1000 is having a hard time. Personaly I find flying on 737 or A320 a pretty horrid experience: 6 seats for one aisle, versus 9 seats (787 or A350) for two aisles in a wide-body. I like walking around, and don't care for windows though, so I guess it's a matter of taste.