Narrative:

Prior to approach at chs, ATIS described CAT ii approachs to runway 15. Prior to final approach fix, approach control gave RVR's as mid 1600 ft rollout 1800 ft. When we queried the touchdown RVR, he said he wasn't sure it was working at the time, it was reading zero, but the last 2 aircraft landed ok and the visibility had not changed. We hurriedly checked operations specifications and concluded that we were legal to substitute mid or rollout RVR for touchdown RVR. After landing, with further research, we concluded that we may have not been legal to conduct a CAT ii approach with no touchdown RVR being reported. Confusion existed in the short time we had to make a decision, since approach control never reported the touchdown RVR as inoperative, and the visibility was as good or better since the 2 previous aircraft landed. This situation could have been avoided if: 1) the ATIS had reported that touchdown RVR was inoperative. Sufficient time would have existed to research the situation. 2) we had gone into a holding pattern at the FAF and further queried the controller as to the exact status of the touchdown RVR. 3) each CAT ii and CAT III approach plate had a printout of which RVR is required and controls, rather than having to hurriedly get the operations specifications out to check it.

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Original NASA ASRS Text

Title: FLC MAKES CAT II APCH WITH INOP TOUCHDOWN RVR. MID AND ROLLOUT RVR WERE AVAILABLE.

Narrative: PRIOR TO APCH AT CHS, ATIS DESCRIBED CAT II APCHS TO RWY 15. PRIOR TO FINAL APCH FIX, APCH CTL GAVE RVR'S AS MID 1600 FT ROLLOUT 1800 FT. WHEN WE QUERIED THE TOUCHDOWN RVR, HE SAID HE WASN'T SURE IT WAS WORKING AT THE TIME, IT WAS READING ZERO, BUT THE LAST 2 ACFT LANDED OK AND THE VISIBILITY HAD NOT CHANGED. WE HURRIEDLY CHKED OPS SPECS AND CONCLUDED THAT WE WERE LEGAL TO SUBSTITUTE MID OR ROLLOUT RVR FOR TOUCHDOWN RVR. AFTER LNDG, WITH FURTHER RESEARCH, WE CONCLUDED THAT WE MAY HAVE NOT BEEN LEGAL TO CONDUCT A CAT II APCH WITH NO TOUCHDOWN RVR BEING RPTED. CONFUSION EXISTED IN THE SHORT TIME WE HAD TO MAKE A DECISION, SINCE APCH CTL NEVER RPTED THE TOUCHDOWN RVR AS INOP, AND THE VISIBILITY WAS AS GOOD OR BETTER SINCE THE 2 PREVIOUS ACFT LANDED. THIS SIT COULD HAVE BEEN AVOIDED IF: 1) THE ATIS HAD RPTED THAT TOUCHDOWN RVR WAS INOP. SUFFICIENT TIME WOULD HAVE EXISTED TO RESEARCH THE SIT. 2) WE HAD GONE INTO A HOLDING PATTERN AT THE FAF AND FURTHER QUERIED THE CTLR AS TO THE EXACT STATUS OF THE TOUCHDOWN RVR. 3) EACH CAT II AND CAT III APCH PLATE HAD A PRINTOUT OF WHICH RVR IS REQUIRED AND CTLS, RATHER THAN HAVING TO HURRIEDLY GET THE OPS SPECS OUT TO CHK IT.

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.