This easy-to-use calculator is perfect for determining crosswind and headwind components just before takeoff or landing. To operate, put the runway heading in the box at the top of the computer, find the wind direction and follow the corresponding line towards the center of the computer to mark the wind speed. Then read down for the crosswind component and across for the headwind component. No pencil needed. Measuring just 4 3/4” in diameter, the Crosswind Calculator is perfect for the cockpit. The back of the calculator also lists the flight plan sequence, VFR cruising altitudes and has space to copy down appropriate V-speeds.