Narrative:

Landing at sfo airport without landing clearance. The relief pilot believed we had been cleared for the approach and landing. I did not hear this, I heard cleared for the approach. As we made the high speed turn off I asked the first officer to ask for clearance to cross the runway 28L. At that point he switched from approach control frequency to tower frequency and I realized we had not had clearance to land. The WX was 1600 to 2800 RVR, thin overcast, fog. We set up for a CAT I approach with minimums of 300' AGL. I have less than 100 hours in command on the widebody transport so that is the reason for the high minimums. The plan was to use one autoplt out of the three. We used the right autoplt so I would have a flight director throughout the approach. We planned to disconnect the autoplt no later than 200' decision height. The approach was interrupted by 4 autoplt disconnects. As a result the copilot was continually distracted by trying different autoplt combinations while I was concentrating on more or less hand flying the approach. This was a non stop flight originating in hkg. The crew was tired. In view of this, the solution would have been to have one person out of the 4 backing up the copilot on the radio to make sure the proper clrncs were received.

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Original NASA ASRS Text

Title: ACR WDB RWY TRANSGRESSION UNAUTH LNDG AT THE END OF EXTENDED OVERWATER OPERATION.

Narrative: LNDG AT SFO ARPT WITHOUT LNDG CLRNC. THE RELIEF PLT BELIEVED WE HAD BEEN CLRED FOR THE APCH AND LNDG. I DID NOT HEAR THIS, I HEARD CLRED FOR THE APCH. AS WE MADE THE HIGH SPEED TURN OFF I ASKED THE F/O TO ASK FOR CLRNC TO CROSS THE RWY 28L. AT THAT POINT HE SWITCHED FROM APCH CTL FREQ TO TWR FREQ AND I REALIZED WE HAD NOT HAD CLRNC TO LAND. THE WX WAS 1600 TO 2800 RVR, THIN OVERCAST, FOG. WE SET UP FOR A CAT I APCH WITH MINIMUMS OF 300' AGL. I HAVE LESS THAN 100 HRS IN COMMAND ON THE WDB SO THAT IS THE REASON FOR THE HIGH MINIMUMS. THE PLAN WAS TO USE ONE AUTOPLT OUT OF THE THREE. WE USED THE RIGHT AUTOPLT SO I WOULD HAVE A FLT DIRECTOR THROUGHOUT THE APCH. WE PLANNED TO DISCONNECT THE AUTOPLT NO LATER THAN 200' DECISION HEIGHT. THE APCH WAS INTERRUPTED BY 4 AUTOPLT DISCONNECTS. AS A RESULT THE COPLT WAS CONTINUALLY DISTRACTED BY TRYING DIFFERENT AUTOPLT COMBINATIONS WHILE I WAS CONCENTRATING ON MORE OR LESS HAND FLYING THE APCH. THIS WAS A NON STOP FLT ORIGINATING IN HKG. THE CREW WAS TIRED. IN VIEW OF THIS, THE SOLUTION WOULD HAVE BEEN TO HAVE ONE PERSON OUT OF THE 4 BACKING UP THE COPLT ON THE RADIO TO MAKE SURE THE PROPER CLRNCS WERE RECEIVED.

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.