missile script for aeroplane

I have previously made space shooter shooting systems, and FPS grenades, but now I am trying to make a missile that will be launched from a plane. I am new to Unity and can't figure out how to make it travel forward in the direction it's fired.

var bomb : GameObject;
var explosion : GameObject;
function Update () {

This is all I have at the moment. Dont worry about "explosion", I know how to set that up. I can't figure out how to make it travel forward relative to it's own Z axis. Any help is appreciated.

You could take a look at the reference for the function Instantiate.

There are example scripts for launching projectiles.

Try something like this:

var missileSpeed : float = 10;
var missileBomb : Rigidbody;

function Update(){
var clone : Rigidbody;
missile = Instantiate(missileBomb, transform.position, transform.rotation);
missile.velocity = transform.TransformDirection (Vector3.forward * missileSpeed);

I took this straight from the Instantiate in the API.