1. What is Ground Speed?

Ground Speed (GS) is the horizontal speed of an aircraft relative to the ground. It combines the aircraft's true airspeed (TAS) with the wind component to determine the actual speed over the ground.

2. How Does the Calculator Work?

The calculator uses the ground speed equation:

Where:

• \( GS \) — Ground speed (knots)
• \( TAS \) — True airspeed (knots)
• \( wind \) — Wind speed (knots)
• \( \theta \) — Wind angle (degrees)

Explanation: The equation accounts for both the headwind/tailwind component (cosine term) and the crosswind component (sine term) to calculate the actual ground speed.

3. Importance of Ground Speed Calculation

Details: Accurate ground speed calculation is crucial for flight planning, fuel estimation, and arrival time calculations. It helps pilots adjust for wind effects during navigation.

4. Using the Calculator

Tips: Enter true airspeed in knots, wind speed in knots, and wind angle in degrees (0° = headwind, 180° = tailwind). All values must be valid (TAS > 0, wind ≥ 0, angle between 0-360).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between TAS and GS?
A: TAS is the aircraft's speed through the air, while GS is the speed over the ground. GS equals TAS plus or minus the wind component.

Q2: How does wind angle affect ground speed?
A: Headwind (0°) reduces GS, tailwind (180°) increases GS, and crosswind (90°) has minimal effect on GS but affects drift.

Q3: What are typical ground speeds?
A: Commercial jets typically have GS between 400-600 knots, while small aircraft may have GS between 80-200 knots, depending on wind.

Q4: Why is ground speed important for pilots?
A: It helps determine fuel consumption, estimated time of arrival, and is critical for instrument approaches and holding patterns.

Q5: How accurate is this calculation?
A: The formula provides theoretical GS. Actual GS may vary slightly due to factors like altitude changes and wind gradient.