Mixed-mode at Heathrow not likely – “means a lot of pain for not much gain”
Heathrow Airport has dropped its support for mixed-mode. The Times reports that Heathrow is not likely to be able to greatly increase the number of flights using the airport, by bringing in more mixed-mode (where planes both land and take off on the same runway). At present, one runway is used solely for take-offs and the other for landings. The roles are swapped at 3pm each day, to give residents who are over flown some respite from noise. It is thought that in its submission to the Airports Commission, Heathrow will say that even though mixed-mode could increase capacity by some 10%, it would be more trouble than it is worth and there would be a huge public backlash. Ministers had hoped that Heathrow would introduce “mixed-mode” arrangements to boost flight numbers as an interim measure. Heathrow would require a planning inquiry to increase the cap of 480,000 flights a year. That could take 3 years, even judicial review. It would also need up to 2 years to build new taxiing routes to and from terminals, to use mixed-mode.
Heathrow plan ‘means a lot of pain for not much gain’
Heathrow airport managers are likely to tell the Airports Commission that mixed-mode would at best be a short term fix, to increase capacity, and be more trouble than it is worth. Mixed-mode could add 10%.
Ministers had hoped that Heathrow would introduce so-called “mixed-mode” arrangements to boost flight numbers. At present, one runway is used solely for take-offs and the other for landings. The roles are swapped at 3pm each day, to give residents who are over flown some respite from noise.
Heathrow says that changes like mixed mode could not be introduced until perhaps 2020. It would require a planning inquiry to increase the cap of 480,000 flights a year. That could take three years, even without the threat of judicial review. It would also need up to two years to build new taxiing routes to and from terminals, to use mixed mode.
Ministers would face a backlash if they tried to force more flights on residents. “It would be a lot of pain for not much gain,” said a Heathrow source.
It is not thought that Heathrow will propose mixed-mode as part of its submission to the Airports Commission
The full Times article is at
“Nobody can overstate how hard we would fight to keep our half-day’s
break from the noise” West London resident
“Mixed-mode, however, should not be introduced. It would deliver a small increase in capacity for a large increase in noise, and the planning process would take almost as long as for a third runway.”
That quote on the front page taken from the Institute of Directors, long-time supporters of Heathrow expansion, concisely sums up the problems with mixed-mode. It is significant that the Institute, such staunch backers of expansion and still supporters of a 3rd runway, have ruled out mixed mode.
Mixed-mode has been touted both as an alternative to a third runway at Heathrow and as a quick-fix way of increasing airport capacity in London in the short term. It is neither.
What is mixed-mode?
To understand it we first need to understand runway alternation.
At present planes landing over London switch runways at 3pm to give residents under the flight path a half day’s break from the noise. Over half a million people benefit from it.
Under mixed-mode, aircraft would cease to switch runways at 3pm. They would land on (and take off from) both runways all day long. For many people under the flight paths, that would mean a plane overhead every 90 seconds for a lot of the day.How much extra capacity would mixed-mode create?
Mixed-mode would enable flight numbers to increase from 480,000 a year (the current limit) to around 560,000 a year.
The Myths about Mixed-Mode
It is not. It would take many years to put in place. There are two reasons for this:
For residents under the current flight paths, it would be more unpopular than a 3rd runway as it would mean a significant increase in aircraft numbers and, for people in the worst-affected boroughs in West London, an end to their half day’s break from the noise. Many people only moved into the area because they knew they got this respite period.
Its impact would be felt across wide areas of London and the South East. There are two reasons why, far from being minor, it would affect a lot of people:
But there would also be new areas impacted by aircraft noise for the first time: Air Traffic Control has made it clear that mixed-mode would require the final approach path to be lengthened to ensure that planes landing on the parallel runways simultaneously were separated well before they reached the airport.