Hi, i'm making a space game with some realism but am having difficulty working out the script for the ships. The problem is there is no gravity so the ship is always moving and I need to be able to move the mouse around independently (with the ship in motion) and only when thrust is pressed will the ship change course (in the direction the mouse is then pointing to and altered by inertia) rather than the ship constantly following the mouse position.

Here is my script so far:

var rSpeed = 1.0; // **Scale. Speed of the movement** 

function FixedUpdate () 
{ 
   MousePosition = Input.mousePosition; 
   MousePosition.x = (Screen.height/2) - Input.mousePosition.y; 
   MousePosition.y = -(Screen.width/2) + Input.mousePosition.x; 
   transform.Rotate(MousePosition * Time.deltaTime * rSpeed, Space.Self); 
   rigidbody.freezeRotation=true;
}

var flyingSpeed = 0; 
var minThrust : float= 0; 
var maxThrust : float = 1000; 
var Accel = maxThrust / 4; 
var Jumpspeed = maxThrust * 5; 

var turnSpeed = 10; 

function Update () { 
//Accelerate the ship useing the thrust button. 
if(Input.GetButton("Thrust")){  
flyingSpeed = Accel + Mathf.Clamp(flyingSpeed, minThrust, maxThrust - Accel); 
} 
//decelerates the ship till stop. 
if (Input.GetButton("Decellerate")){ 
flyingSpeed = -Accel + Mathf.Clamp(flyingSpeed, minThrust +Accel, maxThrust );} 

if(("Thrust")){ 
   rigidbody.velocity = transform.forward * Time.deltaTime * flyingSpeed; //Apply velocity in Update() 

} }

Thanks for any help with this.