Flying lead in a section of 170s, we were headed into the uncontrolled field for lunch and talking to a Mooney also inbound. I called at 10nm and he was at 8 nm, no problem. We enter on the 45 for a right downwind (RH Traffic on 13) to 13 (wind 190/6, 270OVC) and watched the Mooney land as we extended a bit to fly a nice low pass before coming around to land. The runway was clear and we were the only ones in the pattern as we head down (trees along west side of runway) I'm on the west edge and -2 is over the centerline to keep clear of parked traffic on the ramp. As we get about 1/4 of the way down the runway something catches my eye ahead.....it's another plane (looked all grey but was actually grey,dirty white and dull orange) crossing the numbers, landing on 31

We land, park and go over to the FBO. Sure enough one of the locals had tried to call on his cell phone when he lost electrical power but no one could understand who it was or what he wanted. By the time we had landed he had gone in and ripped them a new one for "not clearing the pattern" for him. Kid told him that he wasn't a tower, the field was uncontrolled and that he was responsible for ensuring he avoided traffic in the pattern. Apparently, he was going to report US to the FAA but, when we went to find him, he was no where to be found.
Now, we are trying to decide if we need to use the NASA silver bullet for this. .... any advice on that?
Debriefing the event, a few things came to light:
- expect the unexpected, someone is always trying to kill you
- a well briefed form hop may not include everything you encounter!
- neither the Mooney nor our flight saw nor heard anything about this other plane (a C-210)
- even though the FBO had some type of cell phone comms with "someone" they failed to mention anything when we called at 10 nm for a traffic advisory (Mooney did not get anything either)
- wx conditions at the time were VFR but, with 2700OVC and a body of water at the south end of 13 along with fall tree colors made the aircraft approaching from somewhere to land downwind was virtually invisible
- if a questionable event occurs, all involved should stick around to discuss what happened and how to avoid the same situation in the future. As it is now, the other guy is most likely PO'd at us for not giving him the right of way he thought he deserved
Other thoughts, comments? Let me have 'em! Thanks....

Fly Safe......