Alright legal eagles of APC. I've got a question for y'all.

My question: when shooting an approach into an uncontrolled airport with calm winds and another aircraft already working a specific runway, does the FAR/AIM require you to comply with the pattern the first aircraft is working regardless of which RW your approach takes you to? I can't find a definitive answer for this.

Background: uncontrolled airfield, daytime, VMC, calm winds. Myself and another company aircraft are on RW 13, left hand pattern, both conducting student training. He's been in the pattern for about 30 min, I just joined about five min prior.

Situation: we receive a call from another aircraft who just started the VOR 31 apch and is about 10mi out. We both announce that we're on RW 13 in the pattern and we continue to make our regular CTAF calls (xwind, downwind, base, etc), though we emphasize that we're on 13. Other traffic makes 6mi call and then that's the last we hear.

Next thing we know, I'm turning base, my company is turning xwind, and this guy shows up on short final for 31, not having made a call since 6mi. He executes a missed, makes a call about departing to the south and leaves.

Fast forward 15 min. Same jackass announces he's on the VOR 31, again, at about 10mi. We both emphatically state our locations in the pattern and that we're on 13 - and ask him his intentions. That's the last we hear. The next time we see him, just a few min later, I'm in the DW and my playmate is on RW 13 doing a T&G and he sees this jackass coming straight at him, though higher, evidently making a low apch. He stays on the RW and tells the other guy to waive off. Jackass never tries to make a landing and departs to the south, without a word.

We don't think the guy was on an IFR plan, rather he was doing the VOR while flying VFR.