I remember when I joined IAL in 1977 and was doing a spot of training at Viscount House (I think that was the name; a BEA establishment). I left work late one evening and it was one of those very clear, crisp November evenings and I happened to look toward the East and there was an amazing sight; lots of aircraft all following each other on approach for what seemed miles. My first thought was "this must be what Led Zepplin had in mind when they wrote Stairway to Heaven". I don't know how many aircraft there were but it was a lot!