Showing custom field contents without listing description

The reason your custom fields are only showing up when there is post content is due to this line:

<?php if( get_the_content() ):?><h3>

Everything after that line will only appear if get_the_content() returns something truthy. The reason being that you’re using a shorthand if statement and not closing to before the custom field logic Try this:

>

<?php if( get_the_content() ):?><h3>
<?php
//this closes the if statment
endif;
?>
<?php
echo types_render_field("nome-do-aeroporto", array("argument1"=>"value1","argument2"=>"value2","argument2"=>"value2"));

?>
<br/>
<?php

echo types_render_field("cidade", array("argument1"=>"value1","argument2"=>"value2","argument2"=>"value2"));

 ?>

I am wondering why your using that if statement in the first place however.

Hope this helps