In aviation, when referring to speed, does 120 knots refer to indicated airspeed or ground speed?

The correct answer pertains to the context in which airspeed is measured in aviation. When we refer to 120 knots in the context of speed, it typically indicates the indicated airspeed (IAS) of the aircraft rather than the ground speed.

Indicated airspeed is the speed shown on the aircraft's airspeed indicator and is crucial for understanding how the aircraft behaves in the air, including lift and stall speed. It is important for pilots to rely on IAS when flying because it considers atmospheric pressure and temperature, which affect how the aircraft interacts with the surrounding air.

Ground speed, on the other hand, reflects how fast the aircraft is moving across the ground and can differ significantly from indicated airspeed due to wind conditions. For instance, if a plane is flying into a headwind, its ground speed may be less than its indicated airspeed. Conversely, with a tailwind, the ground speed can exceed the indicated airspeed.

Selecting ground speed as the answer might seem plausible without proper context since speed is generally referred to in terms of how fast the aircraft is moving relative to the ground during flight operations. However, in most aviation discussions, especially those involving fixed numerical values, the reference is to indicated airspeed.