removing enemy

hi, i'm trying to make a game in which objects drop down randomly and i got another object to shoot it. problem is everything is working fine until the missile hits the enemy. i want to remove the enemy when it collides with the missile but it's not working. I attempted on using array but i'm not to sure how to work this out since i'm still new. So here's my code :

var myMissile = new Missile();

var myEnemy1 = new Enemy1();

var fallingSpeed1:int;

var fallingSpeed2:int;

var enemyStorage1:int;

var enemyStorage2:int;

function randRange(startNum, endNum) {

   return Math.floor(startNum +(Math.random()

                        * (endNum - startNum)));

}

function doFall1 ():void {

    fallingSpeed1 = 3000;

    enemyStorage1 = setInterval (createEnemy1, fallingSpeed1);

}

function createEnemy1 ():void {

    myEnemy1.y = -50;

    myEnemy1.x = Math.random()*stage.stageWidth;

    myEnemy1.rotation = randRange(0,360);

    myEnemy1.addEventListener(Event.ENTER_FRAME, releaseEnemy1);

    addChild(myEnemy1);

}

function releaseEnemy1 (e:Event):void {

    var myEnemy1 = Enemy1(e.target);

    myEnemy1.y+=5;

    if (myEnemy1.hitTestObject(myMissile)){

        explode(myEnemy1);

    }

}

function explode(myEnemy1):void {

    myEnemy1.removeEventListener(Event.ENTER_FRAME, releaseEnemy1);

    removeChild(myEnemy1);

}

doFall1();