B767 CREW HAD ILLEGAL TKOF AT SFO BECAUSE PERFORMANCE DECREMENT FOR MEL'ED INOP ANTI-SKID WAS INCORRECTLY APPLIED.

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MEL DISCREPANCY. MAINT PLACARDED ANTI-SKID INOP WE RAN THROUGH THE REQUIREMENTS AND I CALCULATED THAT THE V1 REDUCTION FOR THE RWY PLANNED PUT US 2 OR 3 KTS BELOW MINIMUM V1 MAKING US ILLEGAL. I CALLED DISPATCH AND SHE RAN THROUGH THE PROC BUT SHE STARTED WITH A HIGHER RWY LIMIT WT THAT WAS BASED ON AIR CONDITIONING OFF AND GOT A V1 SLIGHTLY ABOVE THE MIN V1 MAKING DEP LEGAL. AFTER TKOF I RAN MY OWN CALCULATIONS BASED ON THE HIGER RWY LIMIT. AIR CONDITIONING OFF AND GOT A V1 SLIGHTLY ABOVE THE MINIMUM V1 MAKING THE DEP LEGAL. HER CALCULATIONS SEEMED GOOD SO WE DEPARTED BASED ON THE HIGHER RWY LIMIT; AIR-CONDITIONING OFF AND STILL CAME UP A COUPLE KTS BELOW BEING LEGAL. ON ARR I CALLED HER AND SHE REALIZED SHE HAD DONE THE CALCULATIONS FOR FLAPS 5 DEGS TKOF INSTEAD OF THE REQUIRED FLAPS 15 DEGS; THE CALCULATIONS REQUIRED MAKE IT EASY FOR MISTAKES LIKE THE ONE THE DISPATCHER MADE AND I ALSO SHOULD NOT HAVE ASSUMED THAT HER HIGHER STARTING RWY LIMIT WAS THE REASON FOR THE DIFFERENCES IN OUR OUTCOME WITHOUT RECHKING IT MYSELF.