When a flight is identified as "heavy," what does it signify?

When a flight is identified as "heavy," it signifies that the aircraft has a maximum takeoff weight of 250,000 pounds or more. This term is used in aviation to inform air traffic control and other aircraft in the vicinity that the flight's size and weight characteristics may impact its performance, particularly during takeoff and landing. Larger aircraft, due to their weight, require longer runways for takeoff and landing and have specific wake turbulence patterns that smaller aircraft need to be aware of to maintain safety during flight operations. Understanding this classification is crucial for maintaining safe distances between aircraft and ensuring smooth and safe operations around busy airspaces.