section_path: Operations/Flight movements
section_name: Flight movements
paragraph_text: Flight movements
  
  Aircraft destined for Heathrow are usually routed to one of four holding points. Air traffic controllers at Heathrow Approach Control (based in Swanwick, Hampshire) then guide the aircraft to their final approach, merging aircraft from the four holds into a single stream of traffic, sometimes as close as 2.5 nautical miles (4.6 km; 2.9 mi) apart. Considerable use is made of continuous descent approach techniques to minimise the environmental effects of incoming aircraft, particularly at night. Once an aircraft is established on its final approach, control is handed over to Heathrow Tower.
  
  When runway alternation was introduced, aircraft generated significantly more noise on departure than when landing, so a preference for westerly operations during daylight was introduced, which continues to this day. In this mode, aircraft take off towards the west and land from the east over London, thereby minimising the impact of noise on the most densely populated areas. Heathrow's two runways generally operate in segregated mode, whereby landings are allocated to one runway and takeoffs to the other. To further reduce noise nuisance, the use of runways 27R and 27L is swapped at 15:00 local each day if the wind is from the west. When landings are easterly there is no alternation; 09L remains the landing runway and 09R the takeoff runway due to the legacy of the now rescinded Cranford Agreement, pending taxiway works to allow the roles to be reversed. As of 2025, Hillingdon Council are considering plans submitted by Heathrow Airport Limited for infrastructure works that would facilitate runway alternation during easterly operation. Occasionally, landings are allowed on the nominated departure runway, to help reduce airborne delays and to position landing aircraft closer to their terminal, reducing taxi times.
  
  Night-time flights at Heathrow are subject to restrictions. Between 23:00 and 04:00, the noisiest aircraft (rated QC /8 and QC/16) cannot be scheduled for operation. Also, during the night quota period (23:30–06:00) there are four limits:
  
  A trial of "noise-relief zones" ran from December 2012 to March 2013, which concentrated approach flight paths into defined areas compared with the existing paths which were spread out. The zones used alternated weekly, meaning residents in the "no-fly" areas received respite from aircraft noise for set periods. However, it was concluded that some residents in other areas experienced more noise as a consequence of the trial and that it should therefore not be taken forward in its current form. Heathrow received more than 25,000 noise complaints in just three months over the summer of 2016, but around half were made by the same ten people.
  
  In 2017, Heathrow introduced "Fly Quiet & Green", a quarterly published league table (suspended in 2020 due to the Covid pandemic) that awards points to the 50 busiest airlines at the airport, ostensibly based on their performance relative to each other across a range of seven environmental benchmarks, such as NO emissions. Heathrow has acknowledged, but not attempted to refute, criticism over discrepancies and a lack of transparency over the way in which the figures are calculated. The airport has always refused to publish a breakdown showing how many "Fly Quiet points" each performance benchmark has contributed towards the total score it awards to an airline, thereby putting obstacles in the way of any independent auditing of the published results. Among other criticisms of the league table are the unexplained omission of some of the poorer performers among the 50 busiest airlines and the emphasis on relative rather than absolute performance, so an airline could well improve its "Fly Quiet" score quarter-on-quarter even if its environmental performance had in fact worsened over the period. In October 2024, Heathrow finally reinstated the programme, rebadged as “Fly Quieter & Greener”. Two more environmental benchmarks were added to the previous seven, but in all other respects the aforementioned deficiencies of the original scheme remain.
  
  Due to the COVID-19 pandemic Heathrow has seen a large increase in cargo-only flights, not only by already established carriers at the airport operating cargo-only flights using passenger aircraft but also by several cargo-only airlines.