Before we moved to France I was a volunteer on the ex R.A.F. Britannia XM496 at Kemble, Gloucestershire. The Bristol Air Museum was in one of the hangers there at the time along with several bits from the Concord developement and as a member of the Brit team we were given free range in the museum. Brian Trubshaw gave a talk on the Concord developement one early evening and a big part was the problems with the intakes. The air has to be slowed to sub-sonic before hitting the entry guide vanes and the intake had to be variable to slow it down and it was a nightmare to design. He was a very good talker and there were only about a dozen of us there. very informal and we were just stood by him and wandering around as he pointed out the various things and answered questions.
I remember him saying that the USAF supersonic fighters would practice mock attacks on Concords on the USA flights, but could only keep up with it for a short while as they burnt so much fuel at supersonic as they had to use reheat to get there. Concord of course flew at 1400 mph without reheat.
It's a great shame the Mk2 was never developed. It was to be a lot bigger, quieter and more comfortable. The noise was because it used modified Avro Vulcan RR Olympic engines, non bypass jobbies.
Sorry, but I think I have posted these before, but a while back and it's an ilustration of the Mk2