As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CHA - FLT 1421 - CREW HEARD A RUMBLING NOISE FROM RIGHT PACK EN ROUTE TO MSY. FIFTEEN MINUTES AFTER NOISE, SMOKE ALARMS WENT OFF. CREW SHUT PACK OFF, DECLARED AN EMERGENCY AND DIVERTED TO CHA. THE FLIGHT LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE FOUND THE RIGHT AIRCO PACK ACM OIL SEAL FAILED. THE RIGHT AIRCO PACK WAS REPLACED. OPS CHECKED NORMAL. (M)