I used to live under one of the departure routes out of Stansted (I was just north of Barkway). I have to say that noise from the turbojet powered 1-11 and early model B737 did more to stop Stansted expansion than any of the other campaigns. Sadly Joe Public still believes that ALL aircraft are just as noisy today. Last week I had to drop off my daughter at GLA. Modern aircraft make so little noise that the roar of road traffic – even from some distance - is far more intrusive.
Having said that, the 1-11 was pretty impressive for its time. I believe it had a higher cruise Mach No than do modern aircraft. I never flew them, only as passenger, but flew its successor the 146.
Jack