Ah cpdude, its the technology that bothers you. Change and new ideas are our speciality, we're Technical Services Engineers, its what we do. Technology is the stuff of life to us. That and developing modifications to improve reliability and service in the most economical way.
Now, back to this transonic airplane business. Just below the speed of sound is where all the drag lives. Terrible stuff drag, you have to put in lots of power to overcome it. That puts the fuel bills up and annoys the beanies upstairs. Current airplanes potter along at around 0.83M because it gives the best operating economics. We can push through the "sound barrier" to, say, about 1.2M to counter the transonic drag problem. But then we annoy all those "green" people down below who can't stand all that banging noise. Ok, so we'll only go supersonic over the sea and go down to 0.83M when we're over land.
So, flying from Singapore to London we're only over land for, let me see now, 63% of the way. So discounting acceleration and slow down time we go 31% faster for 37% of the flight time and save 1.9 hours on the journey. A bit less than the 4 or 5 hours that you are interested in saving. And it only takes 20% more fuel.
I suppose that may be worth it. Maybe not. Members of my family fly that way seven or eight times a year and the kerb to kerb time is 23 hours. Cutting that down to 21.1 hours may be worthwhile but I reckon that overall the Concorde programme lost money because people generally are not prepared to pay that much extra to save a small amount of time. People for whom time is money fly Concorde regularly but everyone else saves the cash and settles for subsonic. If Boeing's proposed machine is to succeed they will have to make it work at the same cost as present aircraft in the face of aerodynamic theory that dictates otherwise. Concorde was pulled off the Far East route because it wasn't much faster than the 747 on overland routes. The Boeing proposal is much slower than Concorde.
In the end it is the airlines that have to spend the money. We would be well advised to spend it where it will do the most good. On the ground.
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Through difficulties to the cinema