The earlier days of big airlines involved mostly pretty long distance travel. So the issues were mostly of a different nature.

Thanks for tracking down the specific incident! If I remember correctly, the obvious cycling issue got figured out pretty early (60’s?) - due to other earlier accidents, that part wasn’t a surprise and they thought they had figured out how to deal with it.

There was a presumption that like steel and several other materials, once it hit a specific low stress point the fatigue life became infinite, and that point was just so much lower for aluminum it just LOOKED like it has no infinitive fatigue life point.

It turns out they were wrong.