Heavy (aviation)

When talking to air traffic controllers, pilots will add the term "Heavy" to the end of the flight call sign on flights involving very large aircraft. For example you might hear this : "United 341, heavy, ready for departure".

This term alerts air-traffic controllers that they need to provide extra spacing between aircraft as these aircraft generate significant wake turbulence which can disrupt the flight path of the aircraft right behind. The term is typically used around airports as that is where the cause for concern of wake-turbulence is highest.

Some typical aircraft that use this call sign are the Douglas DC-10, Boeing 747 and Boeing 777.

Of special note here is the Boeing 757 which even though it might not strictly qualify as a 'heavy' from the weight point of view, is still treated as a 'heavy' by air-traffic controllers as it is notorious for its wake-turbulence generating properties due to the specific nature of its wing design, although the stretch 757-300 series is legally considered a heavy since its takeoff weight exceeds 255,000 lbs.

External links

* [http://www.usatoday.com/travel/columnist/getline/2005-06-01-column_x.htm Captain Meryl Getline explains "heavy"]