What is the primary danger associated with jet engine thrust stream near an aircraft?

The primary danger associated with the thrust stream of a jet engine is indeed jet blast or jet wash. Jet blast refers to the high-velocity stream of exhaust air produced by jet engines. This phenomenon can create significant risks for nearby aircraft, as the strong, rapidly moving air can affect the control and stability of an aircraft in close proximity.

Jet blast can be particularly dangerous during takeoff and landing, when aircraft are often in close quarters on taxiways or runways. The power of the jet blast can lead to loss of control for smaller aircraft, especially in cases where they are positioned behind larger jets. This makes awareness of jet blast an essential safety consideration in airport operations.

In contrast, the other options relate to different gravitational and aerodynamic factors. Turbulence created by rotor downwash is more relevant to helicopters rather than fixed-wing aircraft and is typically not associated with jet engine thrust. Induced roll caused by vortices, while a real phenomenon, involves wake turbulence generated by other aircraft rather than direct jet thrust. Ground effect during landing refers to the aerodynamic phenomenon occurring when an aircraft is close to the ground, which affects lift but is not directly tied to jet engine thrust stream dangers.