Heathrow (Circuit Time) 20. Air-Commodore Harvey asked the Parliamentary Secretary to the Ministry of Civil Aviation if, over a period of three months, he will give the average time taken from when aircraft arrive over Heathrow Airport until the time they touch down. Mr. Lindgren The information over three months is not available, but the average for the period 13th October to 24th November, 1947, was 8 minutes.