AS3 Flash Classes Inheritance error

Hey there, I am trying to pass a value from the Doc class to subClass1. This part work fine. subClass1 receives the value and sets an internal variable to the value it got from the Doc class. When I set subClass2 to inherite subClass1 variable I get an error “1203: No default constructor found in base class Aclass.”

I dont know what I am doing wrong. Can anyone Help!

Below is the code of the classes

[COLOR=Red]Doc Class[/COLOR] [COLOR=Red]code[/COLOR]

package
{
import flash.display.MovieClip;
import flash.events.MouseEvent;

public class Main extends MovieClip{
    var maker:Number = 20

    public function Main(){
        
        btn.addEventListener(MouseEvent.MOUSE_DOWN, checker);
        
    }
    
    function checker(event:MouseEvent){
    var a_class:Aclass=new Aclass(maker);
        trace(a_class.types)
        
        var b_class:Bclass=new Bclass();
        trace(b_class.types)
    }
    
}

}

[COLOR=Red]subClass1 code[/COLOR]

package{
public class Aclass {

    public var types:Number
    
    public function Aclass(_type:Number){
    
        types =  _type
        trace('Aclass has been instantiate');
    }
    
}

}

[COLOR=Red]SubClass2 code[/COLOR]

package
{
public class Bclass extends Aclass
{
public function Bclass(){

    }
    
}

}