Narrative:

Operating aircraft X, ZZZ to dca. Approaching dca, ATIS reporting RVR runway 1, 1200 ft variable, 4000 ft. We set up aircraft for automatic approach and landing, just in case visibility required it. We had runway in sight at 6 mi and all the way to touchdown. Approaching runway, tower reported visibility at 1400 ft RVR touchdown and better than 6000 ft rollout. A bank of fog was over the touchdown transmissometer, causing the RVR of 1400 ft. I told the captain and the tower we needed 1600 ft RVR (the minimum for the approach). The captain said we have the runway in sight and that was good enough. He shot the approach and did the automatic land. Was it safe? Yes! Legal? I don't think so.

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Original NASA ASRS Text

Title: AN A319 FO IS CONCERNED WITH THE CAPT'S DECISION TO LAND AFTER RVR IS RPTED BELOW LNDG MINIMUMS.

Narrative: OPERATING ACFT X, ZZZ TO DCA. APCHING DCA, ATIS RPTING RVR RWY 1, 1200 FT VARIABLE, 4000 FT. WE SET UP ACFT FOR AUTOMATIC APCH AND LNDG, JUST IN CASE VISIBILITY REQUIRED IT. WE HAD RWY IN SIGHT AT 6 MI AND ALL THE WAY TO TOUCHDOWN. APCHING RWY, TWR RPTED VISIBILITY AT 1400 FT RVR TOUCHDOWN AND BETTER THAN 6000 FT ROLLOUT. A BANK OF FOG WAS OVER THE TOUCHDOWN TRANSMISSOMETER, CAUSING THE RVR OF 1400 FT. I TOLD THE CAPT AND THE TWR WE NEEDED 1600 FT RVR (THE MINIMUM FOR THE APCH). THE CAPT SAID WE HAVE THE RWY IN SIGHT AND THAT WAS GOOD ENOUGH. HE SHOT THE APCH AND DID THE AUTO LAND. WAS IT SAFE? YES! LEGAL? I DON'T THINK SO.

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.