Hi
Heathrow has only two runways, they are parallel. We operate in segregated mode for most of the day although during the early morning arrival surge we operate some radar separated approaches to both runways. (All the arrivals at this time are Heavy so this means we get rid of the wake vortex.) Both the runways operate at saturation for most of the day; Heathrow currently handles about 1,350 per day. In ideal conditions we can do up to about 48arrivals per hour but more typically it is 42. Departures are normally about 45 per hour but if the traffic mix is good that can be 50.
We deliberately overflow the arrivals so that we have a resevoir of traffic holding in Heathrow's 4 holds. This enables us to maintain a saturated arrival stream, which itself pushes the arrival rate up.
Our radar technique is very deliberate. We use upwind legs where possible so that we can control the timing of the turn downwind. This enables us to fine tune the length of the final approach so that it is kept at the optimum 15nm. Operating a final at this length enables us to use speed control to adjust any vectoring errors so that we get as close as possible to minimum spacing (2.5nm) as the arrivals cross 4DME from touchdown.
The current operation leaves little room for error. Many of our flights are foreign and longhaul - people get tired and can easily misunderstand a foreign tongue. Plans are being made to change the operation to Mixed-mode and then add a third parallel runway to ease the pressure. (Should have been done 20 years ago).
The controllers operate a 10 day shift system; 6 days on and 4 days off. There is a need for great accuracy in radar skills and this means that our pass rate for trainees is not very high. The London TMA has also become very busy, as other airports have expanded. This makes the entire London ATC operation a difficult and challenging one and the demand for high quality controllers is very high.
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