Narrative:

Runways 25L&right were reporting 1/2 mi visibility (RVR 2500 ft) which was below part 135 takeoff minimums, but runways 24L&right were reporting RVR 5000 ft, which was ok for part 135 takeoff. After start-up, I asked the first officer if runway 24L&right was still reporting an RVR of 5000 ft. First officer stated that he checked ATIS and that both runways 24L&right were reporting an RVR of 5000 ft. First officer then requested taxi clearance and were assigned runway 25L. Believing that runway 25L had an RVR of 5000 ft, I accepted that runway. After taxiing onto runway 25L and cleared for takeoff, I applied takeoff power and as I reached V1 and was rotating, the tower gave us an RVR of 2500 ft. Already committed to fly, I elected to continue the takeoff instead of aborting.

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Original NASA ASRS Text

Title: SA227 FLC RECEIVES WX BELOW TKOF MINIMUMS NEAR V1 DURING TKOF ROLL AT LAX.

Narrative: RWYS 25L&R WERE RPTING 1/2 MI VISIBILITY (RVR 2500 FT) WHICH WAS BELOW PART 135 TKOF MINIMUMS, BUT RWYS 24L&R WERE RPTING RVR 5000 FT, WHICH WAS OK FOR PART 135 TKOF. AFTER START-UP, I ASKED THE FO IF RWY 24L&R WAS STILL RPTING AN RVR OF 5000 FT. FO STATED THAT HE CHKED ATIS AND THAT BOTH RWYS 24L&R WERE RPTING AN RVR OF 5000 FT. FO THEN REQUESTED TAXI CLRNC AND WERE ASSIGNED RWY 25L. BELIEVING THAT RWY 25L HAD AN RVR OF 5000 FT, I ACCEPTED THAT RWY. AFTER TAXIING ONTO RWY 25L AND CLRED FOR TKOF, I APPLIED TKOF PWR AND AS I REACHED V1 AND WAS ROTATING, THE TWR GAVE US AN RVR OF 2500 FT. ALREADY COMMITTED TO FLY, I ELECTED TO CONTINUE THE TKOF INSTEAD OF ABORTING.

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.