Conversation so far:
who survived the day the music died 1959
County coroner Ralph Smiley certified that all four victims of The Day the Music Died died instantly.
where did the disaster get the name day the music died
The event later became known as The Day the Music Died, after singer-songwriter Don McLean referred to it as such in his 1971 song American Pie.

Question: what was the cause of the disaster
Self-contained rewrite: what was the cause of the disaster day the music died