Method
Obtaining a precise horizontal wind adjustment from our range card requires a two step process:
- Scaling the range card wind values to match the current wind speed
- Adjusting the scaled wind values for the wind direction
This simplistic take on wind deflection comes with notable limitations, but in hand with simplified UNITAF server settings, serves very well as a baseline method.
Adjusting for wind speed
The range card provides deflection values for wind speeds of 4 meters per second. As the degree of wind deflection experience is affected by temperature, three temperature columns are populated:
Target
Range
Bullet Drop (MRADs) *4mps Wind (MRADs)* (in meters) -15°C -5°C 5°C 10°C 15°C 20°C 25°C 30°C 35°C -15°C 10°C 30°C 400m -3.0 -3.0 -2.9 -2.8 -2.7 -2.6 -2.5 -2.4 -2.3 1.1 1.0 0.8 450m -3.7 -3.6 -3.5 -3.4 -3.4 -3.3 -3.1 -3.0 -2.9 1.3 1.1 1.0 500m -4.5 -4.4 -4.2 -4.1 -4.0 -3.9 -3.8 -3.6 -3.5 1.4 1.3 1.1 550m -5.3 -5.2 -5.0 -4.9 -4.8 -4.6 -4.5 -4.3 -4.1 1.6 1.4 1.2 600m -6.2 -6.0 -5.8 -5.7 -5.6 -5.4 -5.2 -5.0 -4.8 1.8 1.6 1.4 650m -7.2 -7.0 -6.7 -6.6 -6.4 -6.2 -6.0 -5.8 -5.5 2.0 1.8 1.5 700m -8.3 -8.0 -7.7 -7.5 -7.3 -7.1 -6.9 -6.6 -6.3 2.3 2.0 1.7 An in-game range card excerpt using an M24 SWS
If wind conditions in operation are greater or smaller than the 4mps benchmark, we will need to scale the deflection values accordingly. Because wind deflection scales linearly, adjusting values to match target wind speeds is a simple task.
Operation Wind Speed Range Card Value Multiplier 1mps x0.25 2mps x0.5 3mps x0.75 4mps x1 (no adjustment needed) 6mps x1.5 8mps x2 Adjustments for range card wind values using linear scaling.
Adjusting for wind direction
Wind direction will also affect how far our bullet is deflected by the wind. A 90° crosswind permits the full force of the wind to deflect our bullet path horizontally, while quartering winds deflect our bullets less - even with wind velocity unchanged. The range card lists deflection values for a full crosswind, so these values must be reduced for wind directions other than 3 and 9 o'clock:
Direction Deflection Multiplier 12 o'clock x0 (no horizontal deflection) 1 or 11 o'clock x0.5 2 or 10 o'clock x0.87 3 or 9 o'clock x1 (no adjustment needed) 4 or 8 o'clock x0.87 5 or 7 o'clock x0.5 6 o'clock x0 (no horizontal deflection) Adjustments for determined wind values using trigonometric scaling.
Example
Sgt McShooty is deployed as a Spotter (Manual) on a Honeybadger. He ranges a priority target at 700m. The wind is blowing from 2 o'clock at a speed of two dots (1.5~3.2mps). He uses the 10°C column on his range card to find his starting wind value:
Range Card: a 4mps wind @ 700m = 2.0 MRADs
- Wind Speed: 2.0 MRADs x0.5 = 1.0 MRADs
- Direction: 1.0 MRADs x0.87 = 0.9 MRADs
Because the wind is from the 2 o'clock direction, the bullet will deflect 0.9 MRADs to the left due to wind deflection.
Limitations
This method of wind accommodation only accounts for wind conditions at the firing position. Although wind direction is persistent across the entire map with UNITAFs server settings, wind speed may be altered down range due to obstructions and terrain features, decreasing horizontal deflection.
As with all methods that rely on the range card, any conditions that invalidate the populated data on the range card, such as maps with very high base altitudes, will also invalidate the wind deflection information.
Sgt Jochem on 05/07/2024 at 20:44
