These are flights testing and calibrating navaids. I was a passenger on an FAA calibration flight many years ago. It is definitely hard work for the pilots because they have to be very precise when flying approaches.
Um no offense but I'm pretty damn precise on every approach I fly also
I'm not doubting that. I'm pretty sure most pilots try to be very precise on every approach. What I'm saying is that if you are off by a few feet it's not big deal. If the calibrating aircraft is off by a few feet it is a big deal. And most of your approaches are to a definite landing while the calibrating aircraft flies most approaches and then continue flying without touching down.