A320 CREW LANDED WITHOUT CLRNC ON RWY 25L AT LAX.

Narrative

DURING APCH PHASE INTO LAX; APCH CTL CLRED THE FLT TO DSND VIA PARADISE 4 ARR FOR VISUAL TO RWY 25L. APCH ALSO ADVISED US OF A B747 THAT WOULD BE LNDG PARALLEL ON THE N SIDE RWY 24'S. WE WERE VISUAL ON THE ACFT AND DIRECTLY ABEAM AS WE TURNED ON THE FINAL INBOUND COURSE (AND ACTUALLY HAD AN RA ON TCASII). AT APPROX 18 NM FROM THE RWY; THE FLT WAS CLRED ON THE VISUAL APCH; KEEP SIGHT OF HVY; SWITCH TWR AT LIMMA (FAF). THE TRANSITION TO APCH SPD WAS LONGER THAN THE B747 SO THAT THE AIRBUS WAS NOW AHEAD PASSING THE FAF. THE REMAINING PORTION OF THE APCH AND LNDG WAS UNEVENTFUL UNTIL PULLING OFF THE RWY WHEN WE DISCOVERED BY A RADIO CALL ON APCH FREQ THAT WE HADN'T SWITCHED RADIOS TO TWR FREQ AT LIMMA AND WERE ADVISED TO SWITCH NOW. OBVIOUSLY THE ACFT WAS NOT 'CLRED TO LAND' SINCE THE RADIO WAS NOT SWITCHED TO TWR (PNF'S DUTY). THERE IS A 1000 FT CHK THAT CONFIRMS 'INSTS XCHKED; LNDG MEMO GREEN' MADE BY THE PNF. THE PF RESPONDS WITH A CALLOUT OF 'CLRED TO LAND ON PARTICULAR RWY' WHICH WAS CONFIRMED INCORRECTLY; SINCE WE HADN'T TALKED TO TWR (ONLY APCH; WHO CLRED US ON THE VISUAL APCH TO RWY 25L). IN MY OPINION; CONTRIBUTING FACTORS WERE: PREOCCUPATION WITH HVY ACFT ON 3/9 O'CLOCK LINE. VISUAL APCH ON NICE DAY; PRODUCING OVERLY COMFORTABLE ATMOSPHERE. RESULTING LACK OF CONFIRMATION IN CALLOUTS AND PROCS. TWR MADE NO COMMENT TO FLT AND NO ISSUE WAS MADE OF INCIDENT.