Conversation so far:
On what date did the Lynyrd Skynyrd plane crash take place?
On October 20, 1977, the Convair CV-240 passenger aircraft ran out of fuel and crashed in a wooded area near Gillsburg, Mississippi.
Where were Lynyrd Skynyrd going when their plane crashed?
The plane was headed to Baton Rouge
Why were Lynyrd Skynyrd going to Baton Rouge when their plane crashed?
Lynyrd Skynyrd were to perform at Louisiana State University.
Where did Lynyrd Skynyrd take off from before the plane crashed?
The flight started from the Greenville Downtown Airport (South Carolina).

Question: What caused the crash?
Self-contained rewrite: What caused the Lynyrd Skynyrd plane crash?