> airline industry got a lot of stuff just right the first time Not quite the first time: by looking at 1958, the start of the jet age, you have deliberately s

> airline industry got a lot of stuff just right the first time Not quite the first time: by looking at 1958, the start of the jet age, you have deliberately set as your starting-point the exact point at which they got things right, along that particular dimension (speed). Prop planes such as the DC-3 were most certainly slower. But it's true that commercial airliners have not got much faster over the past 50 years, and that's, as other replies to your comment point out, down to the speed of sound.