Jet Scott is an agent with the "Office of Scientifact".
That is a department likely associated with the Pentagon as Scott is seen on several occasions being directed by and reporting in to a General Gray working out of that DOD headquarters. Adding to this assumption is the fact that Scott has at his beck-and-call all manner of military equipment and considering the speed with which it is delivered, it is safe to say that the department has a good deal of clout.
This department is the one that is called whenever there is any activity outside normal affairs, though not just military in nature. Underwater explosions threatening shipping lanes, missing deadly viruses, radioactive outbreaks, and so on. Some are definitely military-oriented but many are not so his patch would seem to be the 'unusual' or 'unexplained'.
I would postulate that Scott is a civilian employed by Scientifact as we never see him in uniform even back at headquarters; his normal attire is a well-fitting suit and tie.
Scott is a very good looking man in his probable mid-to-late 30's. Being an operative for a government agency devoted to investigating scientific mysteries and anomalies, Scott is understandably quite educated and very intelligent. His knowledge is wide spread across a good number of different studies which is important because the trouble he will have to deal with are quite varied. He is smart enough and secure enough with his intelligence that he does not need to explain things to people unless they ask. Luckily for those readers like myself who are not so in the loop, invariably somebody nearby will ask so he will graciously explain things.
He is capable of taking care of himself in a fight or scuffle and is not adverse to using weapons when called for but he does not always need to resort to violence even in self-defense; he is just ready to if it comes to that.
He is also more than capable of dealing with the ladies; not an adventure goes by, it seems, that some beautiful woman wants to show her appreciation for his efforts with kisses and he is too much a gentleman to turn them down. He is decidedly, however, a man on the go so there is no one person to dominate his attentions.
One special tool available to Scientifact is the very impressive 'ECOM', short for 'electronic computer'. This amazing machine, remembering that the year was 1954 when we first start following Scott's activities, could be fed lots of disparate information and then spit out some pretty impressive conclusions to help guide Scott. The first case we see it in action had a missing scientist needed urgently to stop a plague and the folks at Scientifact entered lots of data such as "favorite food, poached eggs; collects butterflies; also ancient Mayan carvings ...". The technician gave "each factor a plus or minus value to set up the problem. The tape is set up by electronic scanners". Out came ticker tape that showed the missing professor was heading for Cibola which was interesting because no one seemed to know what that was. Scott will call up ECOM more than once in his career.
[Note on the above: I mean no disrespect for the postulated computer of the 'near-future' as shown in the Scott tales. It clearly is shown to be what computers were thought likely to be able to soon do.]