> Off-Topic: Most stories about politics, or crime, or sports, unless they're evidence of some interesting new phenomenon. Videos of pratfalls or disasters, or cute animal pictures. If they'd cover it on TV news, it's probably off-topic.

Planes are interesting for HN in general, most of us (I think) enjoy learning about how things fail and why, and learning from big business failures is a must if you want to get a startup running. That's why most Boeing MAX stories are usually fine.

"Regular" news stories, on the other hand, tend to be off-topic.