Wake turbulence

Every wing sheds wingtip vortices, and behind a large aircraft they are strong enough to roll a light one. They are strongest behind an aircraft that is HEAVY, CLEAN (flaps and gear up), and SLOW (TC AIM AIR 2.9).

How the vortices behave:

• They sink a few hundred feet below the generating aircraft's path.
• They spread outward and drift with the wind. A light crosswind can hold one right over the runway.

Avoidance (stay upwind, and stay clear of the sinking wake):

• Landing behind a heavy: stay at or above its approach path and touch down beyond its touchdown point.
• Departing behind a heavy: lift off before its rotation point and climb above and upwind of its path.

Trap: the wake sinks, so flying below the heavy's path or landing short of its touchdown point puts you into it. Stay above and land long.

Practice