Well, I’d take a different view.
Given that the “controller” (is it actually ATC there?) has reported the incident, then you’ve little choice but to report. But that wouldn’t be my first reaction.
Nor would I “go around have it out face to face with him”. That’s not likely to be helpful.
But there are a number of facts here that you seem to be assuming, but don’t actually know.
1. You’re assuming he was on the same frequency. Perhaps he was on an Information frequency, and they told him that there was traffic in the area and advised to switch frequency, and as a result never heard your initial calls. I admit not a good practice, but might not be how you’re assuming it. Indeed he might simply have the radio turned off, and turned it on only when he got closer to the airport.
2. I’m not clear on the scale of the map, but it looks like you might be 2-3 miles back from the runway. You also say that you turned final at 1000ft, which also suggests that it’s a long final. Perhaps he heard you and assumed that by “final”, you were far closer to the runway than you actually where. Again not good practice, but assumptions aren’t a good idea.
3. You also assume that there was an instructor onboard without any real evidence for this. It could have been a solo student, or a qualified pilot practicing something that they’d been taught.
4. You don’t know if they pilot had visual contact with you already, and was already separating themselves from you. What came as a shock to you, might have seemed perfectly safe to them (yes, I admit this is a bit of a stretch!).
5. Your plot of the other aircrafts path seems to be an assumption at least up to the point where you saw them.
None of these would present much of a defence, but I think going off half cocked, with a load of assumptions, isn’t a good idea. If your idea of having it out with them is simply to offload some of your own anger, you might be successful, or you might just fuel your own anger further.
I also wouldn’t pay too much attention to his “defence” on the radio. It’s a very human reaction to defend yourself when you suddenly find yourself accused of something that you weren’t expecting. Indeed, proclaiming that you were legally entitled to do so, is a typical defence in such situation. This is especially true if the pilot hadn’t seen you and didn’t realise the danger. Who among us hasn’t defended ourselves against an accusation, only for hours later in the cold calm day to start to wonder if we were actually at fault and should have apologised rather than defend.
If your idea of reporting it is to have someone else teach him the error of his way, then they might, or they might just file it away along with all the other near misses that they get reports of.
But if your idea is to educate the other pilot, then I’d suggest trying to have a friendly chat, explain calmly about how you saw them, how you were concerned, and enquire how it seemed from their side, and how they got themselves into that position, might be more productive. If it goes well, perhaps ask if they’d learnt anything from the incident? You’ll achieve far more in a calm conversation than having it out with them.
Many years ago, I returned to my home airfield (then class G with an AFIS). I was listening out on the radio for about 5 minutes before calling up, and I’d heard one aircraft doing circuits. AFIS told me that there was one aircraft in the circuit and it was on late downwind and suggested that I slot in behind it. I had already identified that aircraft, did slot in behind it. As I did, another aircraft called and asked if I was visual with them. I wasn’t and they stated that they were turning to avoid.
After landing the other pilot came over to me, and very calmly asked about it. I apologised for cutting in, in front and explained what had happened from my point of view. I learnt a few things from the conversation, like not trusting AFIS (or ATC for that matter) to point out all the traffic and not trusting that the aircraft that I was visual with was the one that ATC was talking about, and not to assume that all aircraft operating at the airfield was broadcasting.
I think the other pilot also learnt how their lack of radio calls contributed to the situation. It was an instructor and a student, and in hindsight, I suspect the student needed a lot of coaching and the instructor concentrated on that, and ran out of time for the radio calls.
But the matter was resolved in a calm, friendly manner, with both of us learning something from it. Despite it being friendly, that conversation and incident has stuck in my memory years later, and I think about it every time I’m joining a circuit and I’m looking for the traffic that ATC didn’t tell me about.
I’d suggest a friendly conversation might be more likely to be helpful in this situation than you having it out with one another. Indeed, you might end up learning something from it to, how some of your own actions, while not at fault, contributed to the situation in a way that you hadn’t realised.
As the old BT add used to say, “It’s good to talk”.
Colm
I cannot resist chiming in here.
Where is the old German rule that enroute ought to be flown at least 2000’ AGL? Yes I know SERA may overrule it but it ought still to be deeply impregnated in any German instructor’s personal syllabus.
While I agree the PIC, as a beginner, merits a gentle approach 
I’d have less mercy on the instructor who reportedly taught him this kind of misbehaviour. My approach would be to certainly report this instructor to the relevant Behörde – perhaps informally first.
dublinpilot wrote:
…and ran out of time for the radio calls.
How much time do you need for pressing that button and say: “callsign xy turning final 25”? An instructor teaching his stuff in a busy circuit should be able to do that.
dublinpilot wrote:
But if your idea is to educate the other pilot,…
A person willingly (by his own statement) violating several rules at once can not be educated through a friendly conversation in my experience. An authority must force him to sit an afternoon in the air law class of a flying school instead (this is how the aviation authorities around here typically treat such cases).
A big problem (without wanting to insult anybody on this forum) is that motorglider training is traditionally very substandard in Germany as are the flying, navigating and RT skills of some/many motorglider pilots. It is so bad actually, that whenever I hear a “D-K…” callsign (the “K” stands for motorgliders in our system) on the radio while doing circuit work with a student I will either land and sit it out on the ground or fly elsewhere. I have had quite a few close calls with them as the one in this story and don’t want to push my luck any further.
Jan_Olieslagers wrote:
Where is the old German rule that enroute ought to be flown at least 2000’ AGL?
Gone with the introduction of SERA.
All of this is interesting, but I am wondering whether there isn’t also another learning point here.
IIUC, @Steve6443, you continued you approach (and descent) despite the fact that the other guy was closing in vertically and laterally? Couldn’t you have increased your separation by aborting your descent and turned away?
The challenge with a TIS (Traffic Information System) is that the bearing is not very precise. The altitude however, should be correct, so the best you can do is increase the vertical separation, in Steve6443’s case, by climbing. TIS is a great tool, but only if you act on the information it gives you, and I think it takes a little mental preparation to react correctly.
I have written about that before; I once was cleared to descend on top of another aircraft during an IAP to and airport in N France. Fortunately I had a TIS and declined.
what_next wrote:
Gone with the introduction of SERA.
Yes yes – I anticipated that remark, but I don’t believe in its relevance. Are you really suggesting the student/newly licensed pilot had been taught to cruise at 500’ because SERA was going to authorise that anyway? That takes a lot of believing – in Germany especially. Mind you, the sinner reported to tuition to explain her/his sins.
Jan_Olieslagers wrote:
Are you really suggesting the student/newly licensed pilot had been taught to cruise at 500’ because SERA was going to authorise that anyway?
Hopefully not. But it is even worse than that, because that motorglider pilot/instructor said over the radio, that with SERA he is allowed to fly lower than 500ft. Which is one of the reasons he urgently needs additional training.
My guess of what they were about to do is a practice forced landing using that airfield as their target. This would explain their flight path and the low altitude they were flying at, and also that mention of a “training detail”. Which is no problem at all if you announce your intention.
Well, we seem to agree that the PIC may perhaps have had the excuse of a bad (or at least very poor) instructor. If that was indeed the case, the instructor has no excuse. But from what we have been told it is equally possible that the student f___d up and covered a__e verbally.
Thinking the story over, I am beginning to think the PIC (whether it was the instructor who should know better, or a student pilot who merits better teaching) ought to be reported: this story is bad enough to be reported to the relevant authority – and followed up to see a proper job is done.
Jan_Olieslagers wrote:
…and followed up to see a proper job is done.
Unless anyone files criminal charges (what is certainly not going to happen in a case like this) which will lead to a public case in court, the outcome will not be known to anyone. It will be settled between the local aviation authority and the offending pilot. Most probably by making him sit an afternoon in an air law course.
If he continues like this he will sooner or later trigger a TCAS event of a commercially operated airplane (there are quite a few airports in that region) and then there will be an official investigation. He better gets his theory refresher soon.
what_next wrote:
My guess of what they were about to do is a practice forced landing using that airfield as their target. This would explain their flight path and the low altitude they were flying at, and also that mention of a “training detail”. Which is no problem at all if you announce your intention.
Well, except that this airfield is not admitted for non-club students and the AIP explicitly says overflying of the city below 2000ft MSL (1800ft AGL) shall be avoided.
FWIW I do teach flying overland in 500ft, but not as standard procedure and just for demonstration of how low this actually is and how to deal with low level navigation – and I would never fly through a town, albeit into the traffic circuit of an airport.
