Yeah the Operation Mainbrace case was as close as I could recall too, but the Nimitz case has two top fighter pilots going public on video and mainstream print media to describe the events in detail, plus two radar operators going public and describing the details from their POV as well, plus the first military footage of an object associated with the case going public, and the Pentagon's unofficial report via the AATIP about that event and the signature performance characteristics of AAVs in general. I don't think we have any of that stuff from the Operation Mainbrace incident, or the other USS FDR sightings.
Different times, different attitudes about many things. Unrelated to any of this I recently read
Twenty Million Tons Under the Sea: The Daring Capture of the U-505 by Daniel Gallery and the reason I mention it at all is that I had to sort of bend and tune my reading 'ear' to get around some of the language and views of the era, specifically about the US Navy. Suffice to say 'much more conservative than we are now' would be an apt description of the Navy specifically and military in general. A lot of weird shit went down after the war - 'revolt of the admirals' etc. I don't get the impression that an officer's career would benefit greatly from making reports - and as it is today to
who exactly? Also consider the communication technology of the era - no one then could have imagined what we have now. As I have said in other threads, when I was a kid standing on the bus stop I didn't have an incredibly capable computer in my pocket with access to a global communications grid.
At the time of the Mainbrace incidents a good percentage of all personnel involved would probably have had some relatively recent war time experience and the planes they were flying were as high-tech as it got in the era. Without going to deep I found a couple of quick descriptions
Operation Mainbrace UFOs
UFOs & NATO: The Mainbrace Affair | Mysterious Universe
A lot of time has passed since then but what I see (grain of salt in hand) is military encounters with aircraft exhibiting very similar characteristics to what we have seen recently courtesy of TTSA, with maybe some documentation at hand of the type available at the time.
Multinational military sightings at that. Time has moved on, many of the people involved are worm food and now we have something vaguely remembered that has passed into history. Lacking some other revelation, some fuel for the fire, so will the
Nimitz and related incidents.
When I hear about current encounters I honestly think reconnaissance vehicles using a radically new propulsion system, maybe something similar to what you have theorized. When I hear about them in vacuum tube, drum brake, cigarettes are good for you
1952 that isn't the first thing that comes to mind and I do wonder if there is a connection.