The aeroplane is a very complex machinery. To operate safely an airliner you need a large amount of knowledge, a little from various fields such as physics and mathematics, computer science, automation, flight mechanics, stress, meteorology, FAA regulations, human factors, you name it. This kind of brain workout could be considered equivalent to the university level for a single field of activity. However, "university degree" is just more a social and intellectual "etiquette" that sadly in some countries and cultures is too important, to circles of friends and even marriages. We certainly will not see a captain in the cockpit, a surgeon in the ER or an engineer's signature on a structural stress report, based solely on "university degree" equivalent.