Which instruments are used together to measure wind at an airfield?

• A. PAPI and MALSR.
• B. Ceilometer and Barometer.
• C. Anemometer and wind vane.
• D. NOTAM system.

Answer: (C)

Measuring wind at an airfield relies on two instruments that provide both how fast the air is moving and from which direction. The anemometer captures wind speed, typically with cups or a turbine that spins as air moves; the faster it spins, the stronger the wind. The wind vane points into the wind and shows the wind direction, indicating where the wind is coming from. When you combine these readings, you know the wind condition at the field, which affects runway selection, takeoff/landing performance, and crosswind considerations. The other devices in the options have different purposes: PAPI and MALSR are lighting and visual guidance systems for approaches, not wind. A ceilometer and a barometer measure cloud height and atmospheric pressure, not wind. The NOTAM system distributes airport notices, not measurement data.