Air Traffic Controllers aircraft designation?

Question

Some aircraft are designated by numbers but some have the suffex "Heavy" after its number. How big does an airplane have to be to get this, or is there some other reason for this designation. Of what value to the controller or the ATC system is it.

Answer 1

Taken from Appendix A of the FAAO 7110.65R "Air Traffic Control"

"AIRCRAFT WEIGHT CLASSES

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 flight.

b. Large. Aircraft of more than 41,000 pounds, maximum certificated takeoff weight, up to 255,000 pounds.

c. Small. Aircraft of 41,000 pounds or less maximum certificated takeoff weight."

Any aircraft that is classified as a heavy in this manual must use the word heavy when communicating with air traffic control on or near the airport, with the exception of the Boeing 757, which also must use "heavy". The use of the word "heavy" may be ommitted when an aircraft is operating within the en route envirnoment, aka "center".

The keyword above is "capable"!

Answer 2

The term "heavy" simply refers to a gross weight above 255,000 pounds. From a controller's perspective, adding a "heavy" designation means only two things. It means there must be a 3 minute hold time before another aircraft is allowed to takeoff or land on a runway used by a heavy (for wake turbulence), and in-trail spacing increases. (up to 6 miles I think, but i'm not positive of that)

Pilots of other aircraft can waive the 3 minute wait time at their own discretion, but controllers cannot do it for them.

Answer 3

if i'm not mistaken, heavy refers to any aircraft over 100,000 lbs.
heavy aircraft create a much more powerful wingtip vortex (swirling air coming off the wing tips) which is a danger to aircraft behind them.

Answer 4

Faster approach and landing speed requiring a longer runway.