FAA Ground School Practice Test

For STL, what is the speed of the forecast wind at 12000 ft?

1. 30 knots

2. 35 knots

3. 39 knots

4. 42 knots

The correct answer is: 39 knots

The speed of the forecast wind at 12,000 feet for STL is identified as 39 knots, which is derived from an analysis of meteorological data, typically found in the aerodrome forecast reports or upper-air wind charts. These reports provide critical insights into wind patterns at various altitudes, essential for flight planning and safety considerations. In general, wind speed data fluctuates with altitude due to various atmospheric conditions, including jet streams and local terrain effects. At 12,000 feet, the winds can reach significant velocities, often higher than those at lower altitudes. The figure of 39 knots indicates a robust wind level that could influence flight performance, particularly for takeoff and landing phases, where aircraft could experience crosswinds or require adjustments in their approach. The other figures listed—30 knots, 35 knots, and 42 knots—do not reflect the specific forecast data for STL at that altitude, pinpointing why 39 knots is the most accurate representation of the wind speed forecasted at 12,000 feet based on available weather forecasting methods and data interpretation. It is crucial for pilots to be aware of these wind speeds to ensure proper aircraft control and navigation.