Narrative:

Ground control instructed our flight to taxi to runway 26L. The runway 26L RVR 600' visibility 1/4 mi. The winds were calm. Runway 8R has no RVR capability. I would estimate that the visibility was approximately 600'. I taxi the aircraft on the parallel taxiway to runway 26L, and at not time, was there any improvement in the visibility as observed from the cockpit. Upon reaching the runup pad and shutting down both engines, I requested another visibility reading, it was given as RVR 0, tower visibility 3/16 mi. Several requests from other aircraft for visibility readings resulted in similar readings, with tower visibility always much, much better than actual visibility on the surface. Several aircraft requested to taxi to runway 8L probably an attempt to beat the system and use the 1/4 mi visibility minimum if the tower would report it. Several part 91 aircraft including an medium large transport took off while the RVR was reported way below our takeoff minimums (air carrier) during the 2 1/2 hour period before the fog lifted to the required 1600 RVR. I propose that the aviation community will be best served if at any time that the RVR reading is available on a given runway, even if that RVR is at the opposite end of the runway, that that RVR will be the controling factor to determine the required visibility for takeoff. It appears to me that this would be a safer way to go and I am sure much more accurate than using tower visibility. I am convinced that had I chosen to takeoff on runway 8R, the visibility would have been at best 600', way short of the 1/4 mi visibility first reported by the tower.

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Original NASA ASRS Text

Title: ACR REPORTER STUCK AT END OF RWY WAITING FOR RVR IMPROVEMENT IS CRITICAL OF OTHER ACFT REQUESTING TKOF ON A NON RVR EQUIPPED RWY.

Narrative: GND CTL INSTRUCTED OUR FLT TO TAXI TO RWY 26L. THE RWY 26L RVR 600' VISIBILITY 1/4 MI. THE WINDS WERE CALM. RWY 8R HAS NO RVR CAPABILITY. I WOULD ESTIMATE THAT THE VISIBILITY WAS APPROX 600'. I TAXI THE ACFT ON THE PARALLEL TXWY TO RWY 26L, AND AT NOT TIME, WAS THERE ANY IMPROVEMENT IN THE VISIBILITY AS OBSERVED FROM THE COCKPIT. UPON REACHING THE RUNUP PAD AND SHUTTING DOWN BOTH ENGS, I REQUESTED ANOTHER VISIBILITY READING, IT WAS GIVEN AS RVR 0, TWR VISIBILITY 3/16 MI. SEVERAL REQUESTS FROM OTHER ACFT FOR VISIBILITY READINGS RESULTED IN SIMILAR READINGS, WITH TWR VISIBILITY ALWAYS MUCH, MUCH BETTER THAN ACTUAL VISIBILITY ON THE SURFACE. SEVERAL ACFT REQUESTED TO TAXI TO RWY 8L PROBABLY AN ATTEMPT TO BEAT THE SYS AND USE THE 1/4 MI VISIBILITY MINIMUM IF THE TWR WOULD RPT IT. SEVERAL PART 91 ACFT INCLUDING AN MLG TOOK OFF WHILE THE RVR WAS RPTED WAY BELOW OUR TKOF MINIMUMS (ACR) DURING THE 2 1/2 HR PERIOD BEFORE THE FOG LIFTED TO THE REQUIRED 1600 RVR. I PROPOSE THAT THE AVIATION COMMUNITY WILL BE BEST SERVED IF AT ANY TIME THAT THE RVR READING IS AVAILABLE ON A GIVEN RWY, EVEN IF THAT RVR IS AT THE OPPOSITE END OF THE RWY, THAT THAT RVR WILL BE THE CTLING FACTOR TO DETERMINE THE REQUIRED VISIBILITY FOR TKOF. IT APPEARS TO ME THAT THIS WOULD BE A SAFER WAY TO GO AND I AM SURE MUCH MORE ACCURATE THAN USING TWR VISIBILITY. I AM CONVINCED THAT HAD I CHOSEN TO TKOF ON RWY 8R, THE VISIBILITY WOULD HAVE BEEN AT BEST 600', WAY SHORT OF THE 1/4 MI VISIBILITY FIRST RPTED BY THE TWR.

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.