As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB, LOST LEFT A/C PACK. COMPLIED WITH QRH, PACK DID NOT COME BACK ON. COMPLIED WITH EMERGENCY DESCENT. INSPECTED NR 1 PACK DUCTS IN APU BAY. NO FAULTS FOUND. COMPLIED WITH OPS CHECK. PACK OPS GOOD USING APU AIR OR ENGINE AIR AT LOW & HIGH POWER.