It is very sad for the crew, the last part of that ride was terrifying!
I’m sure, although possibly less so than one might imagine. I was involved in an airprox between two helicopters, whilst acting as an examiner/observer on an IF training session in one of them. I saw the other aircraft suddenly appear from behind the coaming in our 1 o’clock and slightly low. We were in his 7 o’clock, and converging, so totally out of view as he was single pilot. I started saying loudly “turn left, turn left” but there was no reaction. RHS pilot was fixed on his instruments and couldn’t understand why I was so upset about a 3 degree ADF divergence, LHS pilot I don’t know. In the space of about 5-6 seconds I went from calm, to surprise, to shock, to fear then to total relaxed acceptance of imminent death. Then the LHS pilot turned us left and we missed - my report said 20ft vertical and 50ft horizontal separation. The subsequent physiological reaction was intense! Point being, when you know you are actually about to die, it’s not as terrifying as you would expect!