What happens to indicated airspeed when flying at higher elevation airports?

When flying at higher elevation airports, the indicated airspeed remains unchanged, but groundspeed increases because of the lower air density at altitude. As altitude increases, the air becomes less dense, which affects both lift and drag. However, indicated airspeed, which is the speed shown on the aircraft's airspeed indicator, is based on dynamic pressure (the pressure of the air as it flows over the wings). This indicated airspeed does not account for air density changes because it directly measures the impact pressure of the air.

In terms of groundspeed, it is simply the speed of the aircraft relative to the ground. As an aircraft ascends to higher altitudes, it often flies at a higher calibration of true airspeed for a given indicated airspeed due to the decreased density of the atmosphere. Thus, while the indicated airspeed remains constant for the same maneuvering capabilities, the groundspeed increases because the aircraft is moving through less dense air at the same indicated airspeed, leading to a faster movement over the ground.

Contextually, the other options all misinterpret the relationship between airspeed measurements and altitude effects. For instance, saying indicated airspeed decreases significantly neglects how airspeed indicators work. Saying it increases due to density altitude erroneously suggests a