Watching Air Crash Investigation, what do air traffic control or the pilot mean?

Question

They give the call sign for the flight before commencing their broadcast, but sometimes they say the call sign and then the word "heavy". What is the significance of "heavy"?

Answer 1

IT'S THE NUMBER OF THE FLIGHT AND HEAVY MEANS THAT THEY HAVE PASSANGERS ON BOARD.

Answer 2

Nobody is exactly right.  Heavy is used at the end of a call sign for any airplane capable of taking off with a weight of 255,000 pounds or more.  FYI the designation Super is only used for the Airbus 380.  One model of Boeing 757 is not a heavy but the larger one is.  

The reason is airplanes leave wakes in the air just like boats.  Watch the wake a huge warship or tanker leaves and imagine being in a small boat behind it.  The wakes decend and shift with the wind.  If you have a huge wake and let a small airplane into it it can destroy the small aircraft.  Even good sized passenger jets like a 737 can be flipped upside down by the wake of a heavy aircraft.  

Air Traffic Controllers are required to keep an airplane that is following a heavy aircraft a certian distance behind or below the heavy to prevent it from being damaged in the wake.  The smaller 757 gets special attention because it doesn't quite but almost meets the 255,000 pound requirement.  Using the word heavy serves to reinforce the need to give their distance from the big plane to other pilots and to the controller.

Answer 3

it's a large aircraft eg 747

Answer 4

It's a term to describe a (usually) large aircraft which can generate significant wake-turbulence behind it, and prompts controllers to allow extra spacing behind it. Curiously, the 757, while not especially large, is notorious for generating turbulence so is described as "heavy".

Answer 5

Heavy means that an aircraft is capable of taking off more than 225,000 LB.

Answer 6

that the Plane needs a bit more time to move, turn, desecnd or ascend

747

380

330

340

777

Answer 7

Heavy is used to classify large planes such as 747's and A380's.