The Airbus A380 is bigger and heavier than any airplane produced till now. But its very size brought to the fore several problems associated with airport capacity and airline safety. Congestion at airports has highlighted the problem of wake vortices which determine aircraft separation distances which, in turn, affect the productivity of the airport. It is all interconnected. The A380 generates a wake vortex a little higher than that of the B747, which was the reference point till now. Also, its heavier weight does put greater pressure on wear and tear of runways. Thus pavement design has now also come under the microscope.

Most modern airports today are functioning close to their capacity, given the rapid growth of air traffic worldwide. With turnover of aircraft reaching near-saturation point, the wake vortex of airplanes landing and taking-off is becoming a critical factor in air safety. International regulations require commercial airliners to be separated in instrument flying conditions by a distance of at least three nautical miles (5.56 km). This separation distance could go as high as six nautical miles (11.12 km) in the case of a small aircraft following in the wake of a heavy jet like the Boeing 747 or the A380. And yet, congestion cannot be made an excuse for shorter distances between take off times.

Just as a ship leaves a wake behind it at sea, an aircraft leaves a wake in the air. The aircraft's wake is in the form of two counter-rotating swirling rolls of air — the wake vortices — that trail from the wings of the aircraft. The wake vortex pair may last for several minutes and stretch for many kilometres behind the aircraft. The strength of these vortices basically depends on the aircraft weight, divided by the product of air density, flying speed and wingspan. This property generally increases with aircraft weight.

Since the A380 is 30 to 40 percent heavier than the B747 and since its landing speed is145 nautical miles, the wake vortex it generates is considerable. Airbus engineering has managed to control the A380 vortex to the around the same level as the 747.

According to experts, there are some "common misunderstandings" regarding wake vortices. For example, current aircraft separation rules are based on take-off weight only while 95 percent of all vortice incidents occur during landings. There is also doubt expressed over the accepted wisdom that vortex intensity is proportional to aircraft weight. Others believe the vortices are also influenced by wingspan and aerodynamic properties, approach speed and aircraft configuration. A large wingspan helps to mitigate the effects of the vortex and these factors should be taken into account in the final analysis otherwise it could lead to incorrect conclusions. Factors which impact on the vortex are based on aircraft weight, wing loading distribution, wingspan, the downward load on the tailplane, wake modifying devices, engine thrust, exhaust temperature, engine position and spacing, the under belly fairings and main undercarriage, type of flaps, flap setting, the main flap’s outboard edge, aileron design, and the like. Indeed, some smaller aircraft actually have stronger vortices than large ones..

Thus, modifications of wing shape and lift distribution can be used to control the distribution of the vorticity behind the aircraft. However, to do this, it is important to first know the location and structure of trailing wakes of aircraft during takeoff and landing.

Vortices generally sink downwards and tend to move apart. Their decay is strongly influenced by wind direction. It must also be remembered that the vortex strength is greater when the aircraft is in the landing configuration, rather than in the take-off or cruise configuration. Additionally, the effect of a vortex on a following aircraft depends on the ratio of the size of the two aircraft.

Vortex behavior depends not only on its initial strength but also on the core radius and the decay mechanism. An aircraft in the landing configuration generates vortices mainly from flap ends, with some interaction from wingtips and other lift-generating components. Active devices can also influence vortex characteristics.