Windsock Calculator
Calculate wind speed by reading airport windsock segments
Calculate Wind Speed from Windsock
Count segments that are horizontal/upright (0-5 segments typical)
Visual Segment Guide
Wind Speed Results
No wind detected
Formula: Wind Speed (knots) = 3 × Number of Segments
Windsock Reading Reference
| Segments | Knots | MPH | KM/H | Conditions |
|---|---|---|---|---|
| 0 | 0 | 0 | 0 | Calm |
| 1 | 3 | 3.5 | 5.6 | Light air |
| 2 | 6 | 6.9 | 11.1 | Light breeze |
| 3 | 9 | 10.4 | 16.7 | Gentle breeze |
| 4 | 12 | 13.8 | 22.2 | Moderate breeze |
| 5 | 15 | 17.3 | 27.8 | Fresh breeze |
Example Reading
Airport Approach Example
Observation: Windsock shows 3 segments upright
Location: Standard airport windsock (certified)
Height: 4.8m (15.7ft) above ground
Size: 3.6m length, 0.9m diameter (standard)
Calculation
Segments = 3
Wind Speed = 3 × 3 = 9 knots
Wind Speed = 9 × 1.15 = 10.4 mph
Wind Speed = 9 × 1.852 = 16.7 km/h
Classification: Gentle Breeze
Assessment: Good flying conditions
Airport Windsock Standards
Large Windsock
3.6m (12ft) length
0.9m (36in) diameter
Small Windsock
2.5m (8ft) length
0.45m (18in) diameter
Height Standard
4.8m (15.7ft) height
Above ground level
Reading Tips
Count only horizontal/upright segments
Windsock accuracy range: 3-15 knots
Direction points INTO the wind
Check multiple windsocks if available
Fully extended = 15+ knots (strong wind)
Understanding Windsock Calculations
What is a Windsock?
A windsock is a conical textile tube designed to indicate wind direction and relative wind speed. They are commonly used at airports, helipads, chemical plants, and other locations where wind information is critical for safety.
How Windsocks Work
- •Wind enters the large opening and inflates the sock
- •Increased wind speed makes more segments horizontal
- •Direction shows where wind is blowing FROM
- •Segmented design allows visual speed estimation
Calculation Formula
Wind Speed (knots) = 3 × Number of Segments
- Segments: Count horizontal/upright sections
- Range: Accurate between 3-15 knots
- Units: Base calculation in nautical knots
- Conversions: 1 knot = 1.15 mph = 1.85 km/h
Limitation: Cannot detect winds below 3 knots or accurately measure above 15 knots