AN ACR WDB CREW RETURNED AND LANDED WITH APU OIL VAPORS IN THE CABIN AND COCKPIT.

Narrative

DURING THE PREFLT; SMOKE FROM AN APU OIL LEAK ENTERED THE CABIN FROM THE AIR CONDITIONING PACKS AND THE APU WAS SHUT DOWN. MYSELF AND THE FLT ATTENDANTS WERE ON BOARD. MAINT PLACARDED THE APU INOP AND CLRED THE AIRPLANE OF SMOKE AND OIL FUMES. A NORMAL ENG START; TAXI AND TKOF WAS MADE FROM RWY 25L. AFTER 2-3 MINS INTO THE FLT; A FLT ATTENDANT CALLED THE COCKPIT AND STATED THAT SMOKE WAS ENTERING THE CABIN. WE ASKED HER TO CALL BACK IF THE SMOKE CONTINUED TO GET WORSE. THE FLT ATTENDANT CALLED BACK AND SAID THE SMOKE WAS GETTING WORSE AND I WAS SENT BACK TO CABIN TO INVESTIGATE. THE SMOKE WAS VERY NOTICEABLE. THE CAPT DECIDED TO RETURN TO LAND AT LAX. SMOKE AND OIL FUMES BEGAN TO ENTER THE COCKPIT AND WE DONNED OUR OXYGEN MASKS. THE CAPT MADE A PA TO THE PAX AND THE FLT ATTENDANTS EXPLAINING THAT WE KNEW THE SOURCE OF THE SMOKE AND FUMES AND NOT TO BE CONCERNED SINCE WE WERE RETURNING TO LAND AT LAX. WE ACCOMPLISHED THE AIR CONDITIONING SMOKE CABIN/COCKPIT CHKLIST. THE FLT ATTENDANTS THEN CAME TO THE COCKPIT AND TOLD ME THAT SOME OF THE PAX WERE HAVING A HARD TIME BREATHING THE AIR. I DROPPED THE PAX OXYGEN MASKS; WHICH I BELIEVE HELPED TO CALM THE PAX. WE THEN RAN THE CABIN/COCKPIT SMOKE REMOVAL CHKLIST AND RECEIVED VECTORS FOR A VISUAL APCH TO RWY 7R. THE SMOKE BEGAN TO DISSIPATE WHILE ON THE FINAL APCH. WE DID NOT NEED TO DUMP FUEL SINCE WE WERE UNDER OUR MAX LNDG WT. OUR CABIN ALT REMAINED BELOW 7000 FT MSL AND NO EMER WAS DECLARED. AFTER LNDG THE CAPT DETERMINED THAT IT WAS SAFE TO TAXI BACK TO THE GATE AND WE DID SO WITHOUT FURTHER INCIDENT. THE COCKPIT AND CABIN CREW DID AN EXCELLENT JOB UNDER THESE ABNORMAL CONDITIONS.