Which category of turbulence is characterized by violent tossing of the aircraft, making it virtually impossible to control?

The category of turbulence characterized by violent tossing of the aircraft, making it virtually impossible to control, is known as extreme turbulence. This type of turbulence is significantly severe, leading to abrupt changes in the altitude and attitude of the aircraft, which can create an overwhelming and chaotic environment for both the pilots and passengers.

Extreme turbulence can occur due to various atmospheric conditions, such as thunderstorms or when flying through mountain waves. In such situations, the pilot's ability to control the aircraft is severely compromised, and the safety of everyone on board may be at risk. The intensity and unpredictability of extreme turbulence differentiate it from other categories, such as severe, which may cause noticeable changes in altitude and speed but still allow for some level of control by the pilot.

Understanding the different categories of turbulence helps pilots prepare for and respond to the various conditions they may encounter during flight.