Jocko worked at a remote air strip high in the Andes Mountains, outside the border of Peru.
In 1937, he was working at the station when Antoine d'Espere arrived in his plane with Indiana Jones and Francisca Uribe Del Arco. While Jones and Uribe ate, d'Espaire and Jocko refueled the plane. Jocko then checked the radio for weather information, and helped prepare the plane for its next flight leg, by loading a cargo of mail.