Wasn't in Phoenix but genuinely curious about this because I've been looking into triangular craft sightings a lot lately. We don't get much like that over Sheffield but I did see something weird and triangular about two years ago hovering near Hillsborough, completely silent, no nav lights, just gone in seconds.
What I want to know is - did it seem solid to you or was there any kind of flickering or distortion around the edges? I ask because some researchers reckon the visual "shimmer" some people report might point to something interdimensional rather than conventional craft. I know that sounds out there but I've seen some interesting photos where the edges look almost like they're not quite in focus even though the rest of the shot is sharp.
Also how long did it stay visible? Was it just you or did other people around you clock it at the same time?