Narrative:

We were en route from vny at 4000 ft. Upon being switched over to lax approach, we encountered a very congested frequency. We were given a short vector and told to look for 1 aircraft at our 1 O'clock position. A different controller immediately issued another vector and advised us of additional medium large transport traffic at 12 O'clock. At this point we were only about 5 mi from the airport at 4000 ft. After recognizing our traffic, we were cleared to descend to 2500 ft and cleared for the visual approach. We were then given another frequency change and this approach controller again cleared us for the visual approach, in addition to a landing clearance to runway 25L. During our landing rollout approach called and told us to switch to tower frequency. After switching we were advised to call the tower supervisor. The tower supervisor said that approach never issues a landing clearance but we were certain that we had a clearance to land. We assumed that approach and tower were using the same frequency. I personally feel that 3 factors contributed to this communication breakdown: 1) we may have erroneously interpreted our clearance for the visual approach as a clearance to land. 2) approach control never switched us to tower, leading us to believe they were using the same frequency. 3) tower never queried approach about us, or they were too late. If they had queried approach, I'm certain approach would have called us before we had already touched down.

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Original NASA ASRS Text

Title: CORP ACFT LANDS WITHOUT CLRNC.

Narrative: WE WERE ENRTE FROM VNY AT 4000 FT. UPON BEING SWITCHED OVER TO LAX APCH, WE ENCOUNTERED A VERY CONGESTED FREQ. WE WERE GIVEN A SHORT VECTOR AND TOLD TO LOOK FOR 1 ACFT AT OUR 1 O'CLOCK POS. A DIFFERENT CTLR IMMEDIATELY ISSUED ANOTHER VECTOR AND ADVISED US OF ADDITIONAL MLG TFC AT 12 O'CLOCK. AT THIS POINT WE WERE ONLY ABOUT 5 MI FROM THE ARPT AT 4000 FT. AFTER RECOGNIZING OUR TFC, WE WERE CLRED TO DSND TO 2500 FT AND CLRED FOR THE VISUAL APCH. WE WERE THEN GIVEN ANOTHER FREQ CHANGE AND THIS APCH CTLR AGAIN CLRED US FOR THE VISUAL APCH, IN ADDITION TO A LNDG CLRNC TO RWY 25L. DURING OUR LNDG ROLLOUT APCH CALLED AND TOLD US TO SWITCH TO TWR FREQ. AFTER SWITCHING WE WERE ADVISED TO CALL THE TWR SUPVR. THE TWR SUPVR SAID THAT APCH NEVER ISSUES A LNDG CLRNC BUT WE WERE CERTAIN THAT WE HAD A CLRNC TO LAND. WE ASSUMED THAT APCH AND TWR WERE USING THE SAME FREQ. I PERSONALLY FEEL THAT 3 FACTORS CONTRIBUTED TO THIS COM BREAKDOWN: 1) WE MAY HAVE ERRONEOUSLY INTERPRETED OUR CLRNC FOR THE VISUAL APCH AS A CLRNC TO LAND. 2) APCH CTL NEVER SWITCHED US TO TWR, LEADING US TO BELIEVE THEY WERE USING THE SAME FREQ. 3) TWR NEVER QUERIED APCH ABOUT US, OR THEY WERE TOO LATE. IF THEY HAD QUERIED APCH, I'M CERTAIN APCH WOULD HAVE CALLED US BEFORE WE HAD ALREADY TOUCHED DOWN.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.