Rat 5, its the ATC/pilot guff that must have played a large part in this accident. For Nepal Civil Aviation to say it was normal is frankly absurd. Both ATC and pilots made several contradictory and puzzling transmissions. It ended up with a pilot who was proceeding lefthand downwind for 20 later being instructed to join righthand downwind for 02.This required a 180 turn to the right which he appears at least to have started. Then ATC offer him 02 or 20, he elects for 20 and Tower says runway 02 cleared to land. Clear as mud. Aircraft then appears from the north as if trying to land on 20. CVR might reveal what actually happened.