Hacker News guidelines are summarized by this statement: "anything that gratifies one's intellectual curiosity."
I'd agree that if it was an article about a Cessna 172 crashing, it wouldn't belong on Hacker News, but in this case, the interesting fact about this aircraft accident is that it's a brand new airliner model, one that has never been in an accident before. Furthermore, we have some basic flight data, so perhaps a bored hacker might decide to debug what they think happened using this data.