Why it matters: wake turbulence
Big wings leave big swirling wakes behind them, strong enough to roll a smaller aircraft. Controllers space aircraft further apart behind heavy jets, and saying “heavy” on the radio makes sure everyone knows which aircraft is which. The FAA rule: “Pilots of super or heavy aircraft should always use the word ‘super’ or ‘heavy’ in radio communications.”
Which planes are heavy
It’s about what the aircraft can weigh, “whether or not they are operating at this weight”: an empty 777 is still a heavy. That covers the widebodies (777, 787, A350, A330, 767, 747), big freighters and military heavies like the C-17. See widebody jets. The 757 is a special case: the FAA gives it its own wake category.
Super
The Airbus A380 is so big it gets its own word: “super.” In the FAA’s rules it is the only super; the UK also counts the Antonov An-124.
US vs elsewhere
In the US, “heavy” is said throughout. Under the international (ICAO) rules used in Europe and the UK, it’s required on the first call to each controller, to confirm the wake category matches the flight plan.
