A Tic-Tac is 11mm long. I just measured one (and then ate it, I'm quickly running out.). The "Executive Report" on the Nimitz UFO incident says:
The altitude at which the shape was observed is unclear, but I'll go with the lowest, 10,000 feet. Now suppose we were to take a Tic-Tac, how far away to we have to hold it to get the same visual as looking at a 46 foot long object from 10,000 feet? Well 11mm is 0.0360892 feet, so we can just do simple ratios, 0.0360892 feet / 46 feet * 10,000 feet = 7.8 feet. Around 8 feet basically (and if you want a really rough but easy ballpark, around 1/1000th the distance)
So I took a Tic Tac and took a photo of it suspended about a water surface from 8 feet up (I just held my iPhone over my head). The photo above has that Tic Tac in (I just digitally remove the supports). Can you see it?
Here''s another, with feet for scale
And finally an extreme example
The point of these is that spotting something that's 46 feet long from 10,000 feet has the possibility of errors. I've been encouraging people to draw diagrams of what they actually saw, set in some context where scale can be judged. Like an F/A-18 cockpit. What would the Tic-Tac look like from the Pilot's point of view?
And then, if we want to eliminate non-advanced-technology, what do other things look like in that same context? Birds, balloons, small planes, white waves.