Import from Class to AS3?

programming flash
1

I trying to learn and follow some tutorials about classes and stuff like that. If you look att my code I have posted a object called “FallingObject” falls every third second in the speed of “y += 10;”

Now here is my problem.
I want my falling object to increase the speed every 20 second. How do I do that?

ACTIONSCRIPT 3


var TimerFallingObject:Timer = new Timer(3000);

TimerFallingObject.addEventListener(TimerEvent.TIMER, OnStartFallingObject);
TimerFallingObject.start();
 
function OnStartFallingObject(e:Event){

    var af:Sprite = new FallingObject();
    af.x= Math.random()*640;
    addChild(af);

}

THE CLASS OF “FALLINGOBJECT”:


package {
    import flash.events.Event;
    import flash.utils.Timer;
    import flash.events.TimerEvent;
    import flash.display.MovieClip;
    import flash.display.Sprite;
    import flash.text.TextField; 
    public class FallingObject extends Sprite {
        private var core:Object;
        var speedY:Number = 0;
        public function FallingObject() {
            addEventListener(Event.ADDED_TO_STAGE,onadd);
        }
        
        private function onadd(e:Event) {    
            core=MovieClip(root);
            addEventListener(Event.ENTER_FRAME,loop);
        }
                
        private function loop(e:Event) {
        y += 10;            
        }
        
        public function removeListeners():void {
            removeEventListener(Event.ENTER_FRAME, loop);
    
        }
    }
}