6 / 20
When taking-off behind a heavy aircraft, with the wind coming from the left side, you adopt, whenever possible:
  • A
    an identical flight path to the one of the preceding aircraft.
  • B
    a different flight path from the preceding aircraft, by remaining to the right of and under its path.
  • C
    a different flight path from the preceding aircraft, by remaining to the left of and above its path.
  • D
    a different flight path form the preceding aircraft, by remaining behind it and under its path.

Refer to figure.

Wing tip vortices tend to sink below the flight path of the aircraft that generated them and flow outwards. Therefore, the succeding aircraft should stay above and upwind from the other aircraft's flight path. Upwind - the wind is “hitting” your airplane first and then the other. Downwind - wind is hitting the large plane first and, therefore, will move the vortices in the direction of your airplane (which is undesirable). If the wind is coming from the left, you should fly on the left side (and above) of the track of the preceding aircraft.

Further info on WAKE TURBULENCE:
Whenever an airplane generates lift, air spills over the wing tips from the high pressure areas below the wings to the low pressure areas above them. This flow causes rapidly rotating whirlpools of air called wingtip vortices. An aircraft generates vortices from the moment it rotates on take-off to touchdown.
The intensity depends on aircraft weight, speed and configuration. The greatest wake turbulence danger is produced by large, heavy airplanes operating at low speeds, high angles of attack and in a clean configuration.

Although wake turbulence settles, it persists in the air for several minutes, depending on wind conditions. In calm winds, wing tip vortices separate outwards on each side of the runway. In light winds of 3 to 7 knots, the vortices can stay in the touchdown area, sink into your take-off or landing path, or drift over a parallel runway.

General Guides:

  • To avoid turbulence when landing behind a large aircraft, stay above the large airplane’s glide path and land beyond its touchdown point.
  • If a large airplane has just taken-off as you approach, touch down well before the large aircraft’s lift-off point.
  • When departing after a large aircraft has landed, lift-off beyond its touchdown location.
  • When taking-off behind a large aircraft, lift-off before the large aircraft’s rotation point and climb out above or upwind of its flight path.

Your Notes (not visible to others)

This question has appeared on the real examination, you can find the related countries below.