### Site Tools

aircraft:tmd:airbrake

# Airbrake

In the Aerofly FS 2 an `airbrake` represents a controllable area that creates drag.

## Function Description

The airbrake is probably using something similar to this formula:

`F_d = 0.5 * rho * v^2 * Cd * Area * Control`

Where

• v is the velocity
• Cd is the drag coefficient for the maximum `Area`
• `Area` is the surface size in square meters perpendicular to X0.
• `Control` is the dynamic input values between `0.0` and `1.0` that scales the Area linearly
• `X0` is the direction of the airbrake where it is acting (usually this is the x-axis but it could also be pointing upwards.
• rho is the air density at the Body.R position in the world (+R0 properly rotated with the Body orientation as far as the author of this text wants to believe)

Then the calculated drag is acted upon the `Body` at the `R0` location along the `X0` axis. The real formula used may be a lot more complex to account for the rotation speed of the `Body`.

## Example Code

Caution: Requires a rigidbody with the name `Fuselage`
```            <[airbrake][Airbrake][]
<[string8][Body][Fuselage]>
<[tmvector3d][R0][ 0.0 0.0 0.0 ]>
<[tmvector3d][X0][ 1.0 0.0 0.0 ]>
<[float64][Cd][1.5]>
<[float64][Area][1.0]>
<[string8][Control][ServoAirbrake.Output]>
>```