Private pilot and passenger witness UFO in flight in northern Arizona SkiesI am a private pilot. While co-piloting a 1959 B-95 Beechcraft "Travel Air" between Mesa falcon field (KFFZ) and St. George Utah (KSGU) I witnessed along with two others a spherical craft within approximately one statute mile of our position. While making a course correction turn over the "drake" VOR at 150 knots 8500ft climbing to 10,500 approx heading 330 degrees(Prescott, AZ, according to GPS right after the event our exact posistion was 17 miles due east from the Prescott airport.) I was visually scanning the sky for other air traffic prior and during a left turn. Looking upward (off the starboard wing as it banked upward) the object in question came into veiw. It was a silver lenticular disk, I was the first witness to spot the object. The passenger seated directly behind me was the second. I asked the passenger to look up while still in the turn and to simply tell me what they saw. The witness stated "Oh my god... It's a flying saucer!" (or somthing to that ! effect) By this time I had turned passed my intended heading. I made a corrective turn passed the course in the opposite direction so I could see it again in another left hand turn. We reaquired the target and attempted to photograph the object with a cell phone camera, without success. It is difficult to judge it's exact size, however if it was anything close to a convetional aircraft in size it was within 1 to 2 miles almost directly above our aircraft. As we continued our zig zag turns (in order to maintain a visual contact) on or about or third turn cycle the object began to climb in a spiralling arc through a broken cloud layer that was at about 12,500 plus feet at a very high rate (I estimated 500 to 700 knots possibly supersonic, I based this on my experience as a pilot and witnessing many supersonic fighter aircraft) No condensation trail, and no visable exhaust trail and was out of visual range in under 8 seconds or so. The rest of the flight was uneventful.((NUFORC Note: Witness indicates that date of sighting is approximate. PD))