var hasHeLanded = false;

function takeOff() {
    setTimeout(function () {
        hasHeLanded = true;
        console.log("I just landed! Woooho!");
    }, 5000);
}

function callFriendAndTalkVeryExcitedlyAboutYourPrototype() {
    console.log("Hey friend, you will not believe what my mind stumbled upon...");
}

var keepCalling = setInterval(function callAirfield() {
    if (hasHeLanded) {
        callFriendAndTalkVeryExcitedlyAboutYourPrototype();
        clearInterval(keepCalling);
    }
}, 500);

takeOff();