It cannot be hidden that the Airbus A380 is a huge airplane. Its sheer size, which is the greatest attraction for many, means that it generates correspondingly more wake vortices than smaller aircraft. This means that aircraft flying immediately after A380 must be carefully sequenced to avoid such turbulence. But how much space is required exactly?
A380 aircraft require additional space to avoid turbulence. Photo: Vincenzo Pace | Easy flying
What is wake vortices?
Aircraft disturb the air when flying through due to their size and speed. Their presence causes turbulent air to form behind them, which can be dangerous to other aircraft if they get caught in it. Several components make up the phenomenon as a whole.
One such component is known as jetwash and is an immediate aspect of the phenomenon. The term refers to the gases themselves that accumulate in the area behind an aircraft after it has been powered by its engines. This occurs more quickly, although the resulting turbulence can itself be more severe.
Wingtip vortices tend to remain in place for long periods of time, which can take several minutes after the aircraft has passed. These arise when a wing generates lift, with a low pressure above it sucking air from below the wing into the area above it. This creates turbulent wing tip eddies which, as seen below, can be a more visible phenomenon.
The turbulence caused by airplanes can cause vortex patterns to form in the clouds behind. Photo: U.S. Coast Guard via Wikimedia Commons
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How much space is required behind A380s?
As the largest passenger aircraft in the world, the Airbus A380 generates more wake vortices than other smaller designs. This must therefore be taken into account by the air traffic controllers when they sequence aircraft flying directly behind them.
According to Skybrary, there are different time and distance specifications depending on the size of the aircraft after the A380. In terms of time, it is said that “medium” aircraft need to land behind the biplane for at least three minutes, while “light” models need four minutes. Light and medium-sized aircraft, on the other hand, must take off at least three to four minutes (depending on the runway) after an A380 has taken off. In the case of “heavy” aircraft, this is two minutes.
The air traffic controllers must leave enough space behind the A380 so that the aircraft behind can avoid their strong wake. Photo: Vincenzo Pace | Easy flying.
In terms of distance, Skybrary states the minimum required distance between an A380 and a following light aircraft up to 14.8 km (8 NM). Meanwhile, medium aircraft need 13 km (7 NM) and heavy aircraft 11.1 km (6 NM). These distances are reportedly required in both the departure and approach phases of a particular flight.
Effects on airport capacity
At airports where the A380 is a common facility, the distances required may affect capacity. This is because they can limit the number of planes that can arrive and depart in a given period if multiple A380s pass during that time. As Emirates is the largest A380 operator, its Dubai International (DXB) hub is naturally at risk.
With Emirates operating so many A380s, air traffic controllers in Dubai need to carefully follow the planes. Photo: Getty Images
However, the airport has recently been able to increase its capacities through the introduction of new separation procedures. Eurocontrol, Emirates and flydubai participated in an Enhanced Wake Turbulence Separation program, the studies of which date back to 2013.
The result is the new RECAT cutting process. According to Air Insight, the new system can allow up to three additional arrivals and six additional departures per hour at peak times. As traffic increases and the industry seeks to recover from the effects of the ongoing coronavirus pandemic, this additional capacity will indeed come in very useful.
Have you ever been on a flight that took off directly after an A380 and then had to wait a little longer? Let us know your thoughts and experiences in the comments.