On the way in, there was this odd business with very short runways, which I figured to be a VTOL facility or heliport, presumably as part of Kirtland AFB.
On the way out, there was this thing, which is basically a bridge over a pit with overhead frameworks, sort of like a mine header, supporting what appears to be a section of (simulated?) runway. Again, I presume some aspect of Kirtland AFB, perhaps for training. Without a low-angle photo, which I failed to take from the airplane window, it's difficult to describe, but I had a lot of trouble envisioning what this was for.