Airspeed Indicator: What instrument indicates the horizontal ground speed of travel of a UAV?

Airspeed Indicator: What instrument indicates the horizontal ground speed of travel of a UAV?

• A. Vertical Speed Indicator
• B. Altimeter
• C. Altitude Indicator
• D. Airspeed Indicator

Answer: (D)

The key idea is how velocity is measured in flight instruments. The airspeed indicator shows how fast the UAV is moving through the surrounding air—its speed relative to the air mass. In level flight with no wind, that airspeed matches the forward motion over the ground, which is what people often mean by horizontal ground speed. When wind is present, ground speed can differ from airspeed, and you’d typically rely on GPS or a ground-speed readout for the actual speed over the ground. Among the given instruments, only the airspeed indicator provides a readout of speed. The vertical speed indicator measures climb or descent rate, the altimeter and altitude indicator measure height above mean sea level or ground, and none of those indicate how fast you’re moving horizontally. So the airspeed indicator is the best choice for indicating forward motion, with the caveat that true ground speed requires wind considerations or GPS data.

The key idea is how velocity is measured in flight instruments. The airspeed indicator shows how fast the UAV is moving through the surrounding air—its speed relative to the air mass. In level flight with no wind, that airspeed matches the forward motion over the ground, which is what people often mean by horizontal ground speed. When wind is present, ground speed can differ from airspeed, and you’d typically rely on GPS or a ground-speed readout for the actual speed over the ground.

Among the given instruments, only the airspeed indicator provides a readout of speed. The vertical speed indicator measures climb or descent rate, the altimeter and altitude indicator measure height above mean sea level or ground, and none of those indicate how fast you’re moving horizontally. So the airspeed indicator is the best choice for indicating forward motion, with the caveat that true ground speed requires wind considerations or GPS data.