Most pilots become pretty adept at estimating wind speeds from the wind sock at the airfield, but this isn’t the most reliable method.
After all, wind socks differ and what may appear to be a light wind at our home airfield could be a stinker at an aerodrome we are planning to visit.
For sailors it’s a much easier task of using The Beaufort Scale (below), and this is where I believe that both aviation and sailing should use the same method.
The Beaufort scale is far more reliable than using a wind sock, and once you’ve practiced using it, you will wonder why it took you so long!
Here’s the scale with it’s accompanying force and wind speed. To use it, just look at the Description column and estimate which most closely fits the conditions you are experiencing. Then read off the relevant wind speed.
For most sailors a Force 6 is the limit of there capabilities (or series!), whilst for most pilots a Force 5 is pushing it.
Have a go at using the scale below to estimate your own wind speeds.
| Wind Force | Description | km/h | mph | knots | Description |
| 0 | Calm | <1 | <1 | <1 | Smoke rises vertically |
| 1 | Light Air | 1-5 | 1-3 | 1-3 | Direction shown by smoke drift but not by wind vanes |
| 2 | Light Breeze | 6-11 | 4-7 | 4-6 | Wind felt on face; leaves rustle; wind vane moved by wind |
| 3 | Gentle Breeze | 12-19 | 8-12 | 7-10 | Leaves and small twigs in constant motion; light flags extended |
| 4 | Moderate Breeze | 20-28 | 13-18 | 11-16 | Raises dust and loose paper; small branches moved. |
| 5 | Fresh Breeze | 29-38 | 19-24 | 17-21 | Small trees in leaf begin to sway; crested wavelets form on inland waters. |
| 6 | Strong Breeze | 38-49 | 25-31 | 22-27 | Large branches in motion; whistling heard in telegraph wires; umbrellas used with difficulty. |
| 7 | Near Gale | 50-61 | 32-38 | 28-33 | Whole trees in motion; inconvenience felt when walking against the wind. |
| 8 | Gale | 62-74 | 39-46 | 34-40 | Twigs break off trees; generally impedes progress. |
| 9 | Strong Gale | 75-88 | 47-54 | 41-47 | Slight structural damage (chimney pots and slates removed). |
| 10 | Storm | 89-102 | 55-63 | 48-55 | Seldom experienced inland; trees uprooted; considerable structural damage |
| 11 | Violent Storm | 103-117 | 64-72 | 56-63 | Very rarely experienced; accompanied by widespread damage. |
| 12 | Hurricane | 118 plus | 73 plus | 64 plus | Devastation |