Upvote:6
This is a fair bit before my time, but the first two photographs at least seem quite reasonable. They're both technically from the 1970s anyway, and so doesn't contradict your impression.
That said, while systematic security screening at airports were only implemented in the 1970s, limited checks had already been introduced in certain airports during the preceding decade. This was done in response to the rise of hijackings and terrorist attacks. In the US at least, this was voluntarily done on the urging of the FAA, in airports from where hijacked flights had originated.
The Federal Aviation Administration . . . persuaded a airline to install a limited number of walk-through metal detectors and X-ray machines for carry-on items at selected airports from which hijacked flights originated. With the airlines resistant to mandates that would increase their costs, the FAA did not pursue legislation.
Poole, Robert W. "The case for risk-based aviation security policy." World Customs Journal 3.2 (2009): 3-16.
Hence, note that the first photo is dated December 1970, three months after the notorious simultaneous hijacking terrorist attack in September of that year. In all likelihood you're looking at security measures introduced in direct response to thay attack. Likewise, it's telling that the second example is labelled Zurich-Kloten in 1970. No doubt the depicted security measures were deployed in reaction to the Palestinian terrorist attack that occurred on its runways in 1969.
Both photos are plausibly dated and I see no reason to suspect the captions to be incorrect.
As for the third example from Atlanta, the uploader likely found the photo from the Atlanta History Center. The image was posted to their tumblr account just a few days before the Reddit thread. Note that the date is officially given as "c. 1960", not 1960 exactly as claimed (one suspects the Redditor did not realise what the abbreviation means). Most likely the photo actually does postdates the 1961 hijacking, though I was unable to verify this.
According to the Atlanta History Center, the photographer is called Bill Wilson, and the woman is named as Linda Fay, both of whom seems to have passed. The official description given by the collection is "View of Linda Fay reacting to the first airport security instrument tested at the Atlanta Municipal Airport (now Hartsfield-Jackson Atlanta International Airport) in Atlanta, Georgia."