Wind start and stopes

I just made this script

var wind : float = 500.0;

function start () {

rigidbody.AddForce(Vector3(0,0,wind));

}

Easy…Now i want to add a function that will tell the start frunction to start every lets say 30 sec…
I dont know how to do this any ideas will be very apreciated

Start function is called only when the game starts. You can either loop the AddForce infinity times and put in a "yield WaitForSeconds(30)". Or you can use update like this:

var wind : float = 500.0;
var lastWindTime : float = 0.0;

function Update () {

    if(Time.time - lastWindTime > 30) { //of course you can always change the 30 sec
        lastWindTime = Time.time;
        rigidbody.AddForce(Vector3(0,0,wind));
    }
}

Though this script is untested, it should work fine.