NATS has proposed quite a different method by which planes can be queued to land to deal with the congested airspace at London airports. The ambitious proposal is aimed at cutting down on the missed connecting flights by giving higher priority to the larger planes. All this signals the death knell of the infamous and inefficient stacking system.
The proposal, if it goes into action, would end up boosting the flight paths and completely change the way aircraft circle over the south-east of England once they have joined the queue for landing at airports like Gatwick and Heathrow.
Planes that have a higher passenger count – international flights carrying travellers with onward connections – will be given priority at the request of the airlines. This would allow the flight to jump ahead in the queue and land sooner than aircraft that have been waiting in the line longer.
Under the conventional system, the aircraft usually descends in stages once they hit 11,000 feet till they reach 8,000 feet by circling the altitude (the diameter of the circle is around 10 nautical miles). Once they are given the clearance to make the approach, they start their final descent. In this system, the jets are mandated to be vertically separated by at least a thousand feet.
In the new linear stacking system, all the aircrafts will queue at around 25,000 feet above the ground in a circle that is at least 25 nautical miles wide. Since all of the flights are held at one particular altitude, it allows traffic control to decide on which aircraft gets priority to land.
NATS is also planning to increase the number of flight paths over the south-east of England. This move is sure to be welcomed by people concerned over the noise and pollution levels. The proposal would definitely see the end of the now prevalent stacking system that many of the passengers have experienced, much to their chagrin, before landing at the busier airports in London.
According to Martin Rolfe, the chief executive of the NATS, this modern system has to be adopted by the next decade. If it isn’t, the average flight delay of each of the planes caught up in the congested airspace will increase by at least 15 minutes. This would inevitably lead to an increase in the air traffic, which would end up exacerbating the current situation.
NATS is currently running over 2.5 million flights every year through what amounts to a B-road up in the sky. The airspace that is currently being used for departure and landing was designed in the late 50s and the early 60s for the kind of flights that we now go to museums to look at.
Just as recently as last year, NATS was planning to introduce a new air traffic system which would impose aerial speed limits to manage the traffic flows and avoid tricky jams. It remains to be seen as to how the suggested descent profile would map onto continuous descent approaches. As for the noise levels, the move to spread it more thinly over more people might not be such a bad one after all.