Loading a web page in flash

I am trying to load the contents of a web page into flash, however I keep getting undefined when I trace the data. For example:

var api:URLLoader = new URLLoader();
api.dataFormat = URLLoaderDataFormat.TEXT;
api.load(new URLRequest(this._api_url + ‘logged_in?key=’ + this._api_key));
trace(api.data);

It points to the right address, why isn’t my data loading though? Do I need to have a crossdomain policy? I wouldn’t think I would need to…