GetComponent(Script) Error(Won't detect script)

Here is a javascript I have for a camera handler:

 #pragma strict
 
 var cockpitCamera : GameObject;
 var orbitCamera : GameObject;
 var orbitCameraObject : GameObject;
 
 function Start () {
 cockpitCamera.camera.active = true;
 
 }
 
 function FixedUpdate () {
 
     var cameraInput : float = Input.GetAxis("Change Camera");
     var rotateScript = orbitCameraObject.GetComponent(ArcBall);

     //toggle between the two cameras
     if(cameraInput != 0){
         cockpitCamera.camera.active = !cockpitCamera.camera.active;
         orbitCamera.camera.active = !orbitCamera.camera.active;
         rotateScript.enabled = !rotateScript.enabled;
     }
 
 }

For some reason it won't recognize ArcBall as a name of a script I have written, and I don't know why. Do I have to create an instance of ArcBall or something?