Narrative:

WX reported as clear, 8 KM visibility, temperature 12 dewpoint 12. Flying ILS approach to runway 12. Approach said something we didn't understand before he switched us to tower. We asked him to have tower advise us. Tower cleared us to land. Did not advise us of any change in WX. Approach was normal on glide path, centerline and speed until flare was initiated. At this time we went into a fog bank (at about 10' altitude). I realized I was right of centerline about the same time the chkplt in the right seat did. He said I was to the right at the same time I was correcting as much as I could toward centerline. We landed with one truck slightly off the runway. No damage to aircraft other than #4 and #7 tire change for cuts. No damage to runway or lights. Runway lights and runway were visible throughout the approach until the flare at about 10'. At that point visibility acuity was evidently downgraded to the point where I couldn't detect being right of centerline. All I can figure is that I was looking further down the runway for flare guidance and didn't detect the situation until too late. I considered a go around, but rejected it, as the power was at idle and we were very close to the ground. I feel a go around at this point could have led to a more serious situation. Another factor in going off the side is that I was very reluctant to put very much bank angle in to get back to the center of the runway. Altitude was to low for any bank. I felt I was committed. I don't know whether approach tried to tell us of fog pockets or not. It wouldn't have made much difference anyway. We could see some pockets of fog. We just didn't realize the fog would be thick at 10'. It was like a visibility approach up to the last second.

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Original NASA ASRS Text

Title: PLT OF 2 MAN WDB LNDG AT FOREIGN ARPT LANDED WITH R TRUCK OFF EDGE OF RWY. TWO TIRES CHANGED ACCOUNT CUTS.

Narrative: WX RPTED AS CLR, 8 KM VIS, TEMP 12 DEWPOINT 12. FLYING ILS APCH TO RWY 12. APCH SAID SOMETHING WE DIDN'T UNDERSTAND BEFORE HE SWITCHED US TO TWR. WE ASKED HIM TO HAVE TWR ADVISE US. TWR CLRED US TO LAND. DID NOT ADVISE US OF ANY CHANGE IN WX. APCH WAS NORMAL ON GLIDE PATH, CTRLINE AND SPD UNTIL FLARE WAS INITIATED. AT THIS TIME WE WENT INTO A FOG BANK (AT ABOUT 10' ALT). I REALIZED I WAS R OF CTRLINE ABOUT THE SAME TIME THE CHKPLT IN THE R SEAT DID. HE SAID I WAS TO THE R AT THE SAME TIME I WAS CORRECTING AS MUCH AS I COULD TOWARD CTRLINE. WE LANDED WITH ONE TRUCK SLIGHTLY OFF THE RWY. NO DAMAGE TO ACFT OTHER THAN #4 AND #7 TIRE CHANGE FOR CUTS. NO DAMAGE TO RWY OR LIGHTS. RWY LIGHTS AND RWY WERE VISIBLE THROUGHOUT THE APCH UNTIL THE FLARE AT ABOUT 10'. AT THAT POINT VIS ACUITY WAS EVIDENTLY DOWNGRADED TO THE POINT WHERE I COULDN'T DETECT BEING R OF CTRLINE. ALL I CAN FIGURE IS THAT I WAS LOOKING FURTHER DOWN THE RWY FOR FLARE GUIDANCE AND DIDN'T DETECT THE SITUATION UNTIL TOO LATE. I CONSIDERED A GO AROUND, BUT REJECTED IT, AS THE PWR WAS AT IDLE AND WE WERE VERY CLOSE TO THE GND. I FEEL A GO AROUND AT THIS POINT COULD HAVE LED TO A MORE SERIOUS SITUATION. ANOTHER FACTOR IN GOING OFF THE SIDE IS THAT I WAS VERY RELUCTANT TO PUT VERY MUCH BANK ANGLE IN TO GET BACK TO THE CTR OF THE RWY. ALT WAS TO LOW FOR ANY BANK. I FELT I WAS COMMITTED. I DON'T KNOW WHETHER APCH TRIED TO TELL US OF FOG POCKETS OR NOT. IT WOULDN'T HAVE MADE MUCH DIFFERENCE ANYWAY. WE COULD SEE SOME POCKETS OF FOG. WE JUST DIDN'T REALIZE THE FOG WOULD BE THICK AT 10'. IT WAS LIKE A VIS APCH UP TO THE LAST SEC.

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.