That looked like me playing Microsoft Flight Simulator.
I am learning IFR. (This guy shows how not to do it. He’s right, I’m learning from him.)
(1) Was it “legal”? I saw no runway when I heard “minimums”. Assuming no.
As
@jordane93 said, there are a number of things that you can see that allow you to descend below minimums, including runway lights/approach lights. So for example, last weekend I initiated an approach at CXO when they were advertising 1/8SM FG. I knew I wasn't going to get in - but I had lots of fuel and I wanted to do it for the practice of shooting a real ILS to mins to a missed. Good opportunity since I wasn't in a hurry and had extra fuel.
Mins on the approach were 200 AGL. Upon reaching mins, I saw approach lights, so I continued. At 100 AGL there was no runway there (although I did see the runway lights), so I executed the missed.
In his situation, I would say that he busted mins. He called the runway about 50 ft below mins, and that's also about when it showed up on the video. There is an inherent lag in the human brain between saying internally "It's time to go missed" and actually going missed, and theoretically he was within that. However I think he had made the decision that he was going to land and that he was going to see the runway, so I don't think he had any intention of going missed. This is a really bad idea - you should always plan for the missed, and be surprised when you see the runway.
(2) Is there typically some lag time in the GPS annunciation vs DA/MDA? Or do you go missed as soon as you hear that? I’m guessing it’s just an aid and the altimeter must rule the day.
The annunciation was from the G600, which is tied to the baro altimeter. I went and looked at the approach, watched that segment of the video a few times. The G600 behaved exactly as it should - it announced "MINIMUMS" at minimums. He then went down another 50 ft or so before calling the runway.
Keep in mind that, because he was so far above the glide slope, he was hitting minimums a lot closer to the runway than he should have. This has all kinds of bad ramifications, especially on a 3500 ft runway.
(3) Personal mins - I get it in VFR flying. On an IFR approach, do people set their own higher minimums (greater than DA/DH), or is this “considered” bad practice, leading to deteriorating of skills, and unable to eventually pass an IPC or check-ride? I could see someone saying “if you can get comfortable with breaking out at 200 ft DA in actual, then you have no business flying IFR or holding an instrument ticket”. Or is my impression wrong?
There are lots of different ways to look at this. My opinion on personal minimums is that they should be applied in terms of conditions at departure and forecast conditions at arrival, with understanding about alternate options. You should be comfortable flying an approach to minimums, but you can also make no-go decisions and backup plans if things look like they won't work out in your favor.
Using the trip to CXO last weekend that resulted in a missed approach and a diversion, I knew it was likely going to be an approach to mins, but there were viable alternates nearby (lots of airports in the Houston area). So I had my filed legal alternate, but also knew that when I got down there I'd keep an eye on conditions at other fields and decide where to go. If I'd wanted to avoid a low approach altogether, then I could've just not gone.