Narrative:

Approach control cleared us for a CAT IIIA approach with reported RVR 800 (min RVR 700). When well inside the marker, tower reported touchdown RVR 600, mid 1400 and I believe rollout was 1000. Because of the high mid value we elected to continue the approach to alert height. As I was not flying, my duties were primarily inside the cockpit, but after calling 100 ft to alert height I glanced outside and had a clear view of the runway threshold and touchdown zone lights. The approach light system had begun to come into view prior to the 100 ft call. When I called 'alert height' I was mildly surprised that the captain did not execute a missed approach, but since we had an excellent view of the runway environment, I did not voice an objection to the decision to land. A CAT III approach requires a missed approach if landing mins are not reported prior to alert height (regardless of flight visibility). As I do not recall hearing the tower amend the touchdown RVR of 600, the strong possibility exists that we landed below mins. I have given this incident a lot of thought and believe the main reason I did not strongly suggest a missed approach was my sighting of the runway environment. For the 25 yrs I have been flying, seeing the runway environment above decision height meant you could land. I now realize that although I knew the rules, I had not firmly shifted mental gears into a mindset that requires a missed approach if mins are not reported and with no consideration of what you see out the window. The fact that this was an autoland approach also had an adverse affect on my thinking. 'The field is above mins, the airplane will fly and land itself what can go wrong?' I always try to take a moment on every approach a few mi out on final to mentally review missed approach criteria and procedure. In reviewing my actions during this particular approach, I realized I had not done this. Further thought leads me to the humbling conclusion that I allowed myself to become another victim of the insidious ability of a highly automated and reliable system to lull its operator into a false sense of security. Callback conversation with reporter revealed the following information: callback conversation revealed that a reported tower visibility is a company requirement and is in the company operations manual. As such, it would be a limitation for this flight crew.

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Original NASA ASRS Text

Title: ACR FLC SUSPECTS THEY MAY HAVE LANDED IN WX BELOW REQUIRED MINS AT LAX.

Narrative: APCH CTL CLRED US FOR A CAT IIIA APCH WITH RPTED RVR 800 (MIN RVR 700). WHEN WELL INSIDE THE MARKER, TWR RPTED TOUCHDOWN RVR 600, MID 1400 AND I BELIEVE ROLLOUT WAS 1000. BECAUSE OF THE HIGH MID VALUE WE ELECTED TO CONTINUE THE APCH TO ALERT HEIGHT. AS I WAS NOT FLYING, MY DUTIES WERE PRIMARILY INSIDE THE COCKPIT, BUT AFTER CALLING 100 FT TO ALERT HEIGHT I GLANCED OUTSIDE AND HAD A CLR VIEW OF THE RWY THRESHOLD AND TOUCHDOWN ZONE LIGHTS. THE APCH LIGHT SYS HAD BEGUN TO COME INTO VIEW PRIOR TO THE 100 FT CALL. WHEN I CALLED 'ALERT HEIGHT' I WAS MILDLY SURPRISED THAT THE CAPT DID NOT EXECUTE A MISSED APCH, BUT SINCE WE HAD AN EXCELLENT VIEW OF THE RWY ENVIRONMENT, I DID NOT VOICE AN OBJECTION TO THE DECISION TO LAND. A CAT III APCH REQUIRES A MISSED APCH IF LNDG MINS ARE NOT RPTED PRIOR TO ALERT HEIGHT (REGARDLESS OF FLT VISIBILITY). AS I DO NOT RECALL HEARING THE TWR AMEND THE TOUCHDOWN RVR OF 600, THE STRONG POSSIBILITY EXISTS THAT WE LANDED BELOW MINS. I HAVE GIVEN THIS INCIDENT A LOT OF THOUGHT AND BELIEVE THE MAIN REASON I DID NOT STRONGLY SUGGEST A MISSED APCH WAS MY SIGHTING OF THE RWY ENVIRONMENT. FOR THE 25 YRS I HAVE BEEN FLYING, SEEING THE RWY ENVIRONMENT ABOVE DECISION HEIGHT MEANT YOU COULD LAND. I NOW REALIZE THAT ALTHOUGH I KNEW THE RULES, I HAD NOT FIRMLY SHIFTED MENTAL GEARS INTO A MINDSET THAT REQUIRES A MISSED APCH IF MINS ARE NOT RPTED AND WITH NO CONSIDERATION OF WHAT YOU SEE OUT THE WINDOW. THE FACT THAT THIS WAS AN AUTOLAND APCH ALSO HAD AN ADVERSE AFFECT ON MY THINKING. 'THE FIELD IS ABOVE MINS, THE AIRPLANE WILL FLY AND LAND ITSELF WHAT CAN GO WRONG?' I ALWAYS TRY TO TAKE A MOMENT ON EVERY APCH A FEW MI OUT ON FINAL TO MENTALLY REVIEW MISSED APCH CRITERIA AND PROC. IN REVIEWING MY ACTIONS DURING THIS PARTICULAR APCH, I REALIZED I HAD NOT DONE THIS. FURTHER THOUGHT LEADS ME TO THE HUMBLING CONCLUSION THAT I ALLOWED MYSELF TO BECOME ANOTHER VICTIM OF THE INSIDIOUS ABILITY OF A HIGHLY AUTOMATED AND RELIABLE SYS TO LULL ITS OPERATOR INTO A FALSE SENSE OF SECURITY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: CALLBACK CONVERSATION REVEALED THAT A RPTED TWR VISIBILITY IS A COMPANY REQUIREMENT AND IS IN THE COMPANY OPS MANUAL. AS SUCH, IT WOULD BE A LIMITATION FOR THIS FLC.

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.