As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NOSE AIR CONDITIONING UNIT COOLING TURBINE FAILED. APPARENT TURBINE BLADE FAILURE. CAUSE UNKNOWN. FAILURE CAUSED SMOKE IN COCKPIT AND SPARKS EMITTED FROM OUTSIDE THE AIRCRAFT. PILOT PUT EVERYONE ON OXYGEN, CLEARED CABIN WITH RAM AIR AND SHUT DOWN AIR CONDITIONERS. NO FURTHER INDICATION OF TROUBLE. NORMAL LANDING AT VAN NUYS. THIS IS AN ISOLATED INCIDENT AND NO SPECIAL CORRECTIVE ACTION IS NECESSARY.