As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: FUME EVENT- 10 MINS AFTER TAKE OFF CABIN CALLED TO REPORT STRONG CRAYON SMELL IN CABIN, ODOR IN FLIGHT DECK. ODOR REMAINED UNTIL SHUTDOWN. INITIAL TROUBLESHOOTING INDICATES THE APU IS THE SOURCE OF THE ODOR. REPLACED APU PER TASK CARD 26L31049005.