I have twice been at the track when a competitor was lost. Both times I was in my car, once on the false grid waiting for my session, and once on the track a half lap behind the accident. It was so clear from the body language of the people at the track that the inevitable had indeed happened. My comment to my wife as I sat down to watch the start of the race was "they have no business racing here" and I kind of sat there half-praying for luck as I watched the opening laps. A friend of mine's son was in the race, and in fact was driving one of the two cars that started the chain reaction, although he was not in the wreck itself.
RIP Dan Wheldon.