As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKE OFF AT LGB, ON CLIMB SMELL AND VISIBLE INDICATION OF SMOKE IN CABIN PASSING THRU 10K/FT. AIR TURN BACK TO LGB. FOUND LT NR 1 PACK AIR CYCLE MACHINE SEIZED PER TSM 26-15-00-810-804. REMOVED & REPLACED NR 1 AIR CYCLE MACHINE IAW AMM 21-52-21. LEAK CK & OPS CK OK.