NATS suggests change to “stacking” system, with priority given to the largest planes with transfer passengers
NATS have proposed a different method by which planes queue to land, in order to get even more flights safely using crowded UK airspace. At present, if planes arrive early and have to wait for a landing slot, they enter a stack about 10 nautical miles wide and spiral downwards from about 11,000 feet till called in to land, leaving the stack at around 7,000 feet. The plan would be for planes to circle at perhaps 13,000 feet or more, in a stack about 20 – 25 nautical miles wide, and be called off that, to come in to land. The plan is also to give planes with more passengers, and with more transfer passengers priority, if the airline requests this, so they land earlier – than those without transfer passengers. Currently they get landing slots on a first come, first served basis. NATS says there are around 2.4 million UK flights now, but they expect this number to rise to 3 million in 15 years, and they need to accommodate them all. Without the changes there might be delays. NATS also suggest use of more flight routes, giving the potential for noise to be shared out. However, this means people not currently overflown being affected for the first time, and would significantly increase the numbers affected. There will be a DfT consultation on elements of aircraft noise policy and airspace change, probably in the 2nd half of 2016.
London’s infamous plane ‘stacking’ system may be abolished: Aircraft could queue to land in straight lines – with priority given to the largest planes
- New system has been proposed by Nats, which handles air traffic control
- It would bring an end to the current stacking system with an orderly queue
- Instead, planes would hold in a linear pattern and jump the queue
- Priority would be given to planes with higher passenger counts, said Nats
Heavily congested airspace around London could be reformed under an ambitious proposal that aims to cut down on the number of missed connecting flights by giving priority to larger planes – and it would mean the end of the infamous ‘stacking’ system.
The proposal by Nats, which handles the UK’s air traffic control services, would boost the number of flight paths and change the way aircraft circle over south-east England once they’ve joined a queue to land at airports such as Heathrow and Gatwick.
Landing priority would be given to planes with higher passenger counts – usually international flights with travellers who have onward connections – at the request of airlines, allowing them to jump the queue and land ahead of aircraft that have been waiting longer.
Nats also wants to significantly increase the number of flight paths over south-east England – a move that will likely be met by people who have concerns about noise and pollution.
Its proposal would see the end of a stacking system that many passengers have experienced before landing at one of London’s busier airports, the Times reported.
In that system, planes fly in circles, around 10 nautical miles wide, while descending from an altitude of around 11,000ft. Planes must be at least 1,000ft apart vertically, and they land in the order the joined the queue.
However, under the proposed holding system, planes would fly in a linear pattern at an identical altitude, around 13,000ft.
A new holding pattern for incoming flights would give priority to planes with a large number of passengers
The circle would be wider – at 20 to 25 nautical miles – and air traffic controllers would choose the next plane to land, regardless of when it entered the queue.
If a modern system isn’t adopted in the next decade, said Martin Rolfe, chief executive of Nats, the average delay to each plane caught in congested airspace will increase to 15 or 20 minutes, coinciding with an increase in air traffic.
He told the Times: ‘We are trying to run 2.5million flights a year through B-roads in the sky.
‘The airspace that we have over the UK really was designed in the ‘50s and ‘60s for the sort of aircraft that you now go to a museum to look at.’
Last year, Nats revealed that it was considering a new air traffic system that would impose speed limits in the sky to manage traffic flows and avoid jams.
Comments by AirportWatch members:
This looks like a perverted version of “point merge”, but I can see some “issues” with it since the suggested radius of the horizontal non-stack is 25 nautical miles it’ll be an interesting exercise for ATC to decide which of the various aircraft to bring in first. If there’s a big heavy plane wanting to land – but it’s the furthest from the runway it would, surely, make better sense to bring in one or more of the stack members which are closer to the runway.
And such fun arbitrating between the pressing claims of the pilots in the stack, each of which will be keen to get on the ground ASAP.
It’d also be illuminating to see the suggested descent profile from a stack at the suggested 25,000 feet (or is it 13,000 feet?) and how that maps onto continuous descent approaches. I see, too, a cunning plan to spread the noise possibly more thinly but over far more people.
Does not make sense to have all aircraft stacking throughout the day. Timed arrivals will eliminate need for stacks.
It is usual to float ideas in the press before issuing a full consultation, so this is all just a taster for the press, to see what people say.
Curious that the industry hopes there will be 25% more planes in 15 years, since the number of flights has only gone up 3% in the past 15 years.
End of stacking as jets form orderly queue
By Graeme Paton, Transport Correspondent, The Times
April 30th 2016,
Aircraft would queue in a straight-line pattern, enabling controllers to prioritise certain flights
The government is expected to publish a strategy document this year setting out the basic parameters governing airspace redesign.
[The CAA consultation on their proposals for revising the airspace change process ends on 15th June. Details. Then the Department for Transport will hold a formal consultation on changes to the noise elements of the Aviation Policy Framework, and the principles behind changes to flight paths – some time in /after summer 2016, “to coincide with a further announcement on runway capacity in the south east” ie. after a runway decision. In 2nd half of 2016. AW note]
NATS is pushing for clear direction that will allow it to redraw flight paths without leaving them open to legal challenges.
A previous reform to routes out of Gatwick was dropped after local residents objected. A new consultation on the modernisation of airspace across the southeast of England could begin next year.
Full Times article at