Karel_x, many thanks for the translation. So they are doing the NDB approach; but it doesn't look like they've done a detailed brief on who's monitoring what, so presumably their crew actions are whatever their SOP is.
We should always look for the simplest mistakes and the least number of mistakes (Occam's razor).
1 )I don't think they are setting a DH of 100m RA. The transcript just seems to indicate that this is what the nav sets, and it's quite clear from that lovely graphic of Janeczku's (#506) that the nav is calling RA readings. At this stage, the PF is using these as just useful extra info. Since they have an extra guy (General Blasik); then I suggest that since the nav's location on the flight deck is low, this is the best use of the nav.
2)If it's an NDB, then as RetiredF4 and others have said, we could expect them to be getting down to MDH then cruising in.
3) Initially the steeper descent would not concern them as this is what they intend!
4) They aren't acting on ATC because: that's not briefed, an NDB is briefed, and they aren't bothering to provide ATC with heights, there are no pitch movements corresponding to ATC instructions, and nobody before them bothered acting on ATC info (that's enough reasons! Ed)
My scenario involves only 2 mistakes being made:
1) The PF thinking they are level at 100m, due to the repetition of this height and the workload.
2) No instrument crosscheck for a while. Remember that there is a probably a lot of pressure on the crew to get a landing, so there are probably too many eyes out of the cockpit. Also, responsibilities are not included/reminded in the approach brief.
In other words, they only have to get two things wrong for 10 seconds, under high stress.
The PF incorrectly thinks they're level, and neither of the pilots checks Attitude or Rate of Descent in that time, probably because they are both heads out looking for the runway. General Blasik and the nav are reading altimeters as they should, and ATC is providing the best service he can.
Nothing idiotic, no conspiracies, and no alien spacecraft.
From my own very limited number of bad weather approaches in multicrew aircraft, we always specifically briefed and split the task with one pilot doing the instruments and the other solely looking out.
This is the big professional error in my view, the rest is just human error (as opposed to pilot error).