I know this is a ‘tenderfoot’ question but…what does the term “Heavy” mean?


It is attached after the callsign for aircraft over a certain MTOW, to warn following craft of wake turbulence. It is used only in the US as far as I know.

I believe it’s somewhere in the 250,000 lb range.


I figured it had something to do with plane size/weight…but never thought about wake…thanks…


a. Heavy− Aircraft capable of takeoff weights of
more than 255,000 pounds whether or not they are
operating at this weight during a particular phase of
b. Large− Aircraft of more than 41,000 pounds,
maximum certificated takeoff weight, up to 255,000
c. Small− Aircraft of 41,000 pounds or less
maximum certificated takeoff weight.
d. Birds- Small wing-ed creatures ranging from a few ounces to 25 pounds or more that shall be avoided at all costs, regardless of their class distinction.

-From the Aeronautical Information Manual, Pilot/Controller glossary. Some liberty has been taken in the transcription.-



Although it doesn’t meet the definition of a Heavy, I believe the B757 is considered Heavy for the purposes of wake turbulence.


B753 is a heavy, B752 is not, unless they’ve retrofitted it.


Straight from Boeing:

The 757-200 takeoff weights range from 220,000 pounds (99,800 kilograms) up to a maximum of 255,000 pounds (115,660 kilograms) for greater payload or range.

So it can go right to that threshold, and I have heard the occasional 752 with the heavy designation.


okay, B752 is not, unless they’ve customized it :wink: The default/majority configuration is in the non-heavy category (<250,000 MTW)


At one time, ALL 757’s were categorized as heavy, even though they were under 255,000 pounds. Also, the heavy category use to be 300,000 pounds.



Right, due to the unusually high wake turbulence.


Nope, we use the term in Canada as well


Oh, ok, I just knew that the term wasn’t used in Europe. Thanks for the correction.


You missed the manual’s category (e) also — often incorrectly referenced as a ‘microbird’.

e. Bugs- Miniaturized aviation equipment with internalized flight guidance system and a 6-point landing gear. Capable of refueling in flight, but may have a probe that scavenges fuel from other mobile systems. Bugs are often garaged in MS Windowed hangars and allegedly have been responsible for crashes of highly complex digital machines. Caution is advised around bugs at all times. Frequent hand-washing is also helpful.