I believe warning of wake turbulence is very common after take off of any large and heavy aircraft. Wingtip vorticies can sit over a runway (or even drift over

I believe warning of wake turbulence is very common after take off of any large and heavy aircraft. Wingtip vorticies can sit over a runway (or even drift over to parallel runways) for minutes after a takeoff. They are very dangerous to smaller aircrafts. The key to avoiding vorticies is to take off at a point earlier than the previous aircraft and to climb at a steeper angle (vorticies travel behind and downwards from the aircraft that made them). Example: http://www.boldmethod.com/images/learn-to-fly/aerodynamics/avoid-wake-turbulence-during-takeoff-and-landing/takeoff-profile.jpg http://www.boldmethod.com/images/learn-to-fly/aerodynamics/a... Helicopters can also produce serious turbulence as well!