Narrative:

While #1 for takeoff, a landing MD80 reported a 20 KT loss of airspeed at 100 ft. Since over 15 KTS is severe windshear, I was not legal for takeoff. I asked tower if there were any aircraft on approach for a further report. The answer was no, but that the windshear was due to 'local conditions' and did not translate to the other end of the field. This left me in a gray area, but using my knowledge of rno, I made the takeoff. No windshear was noted on takeoff or climb. Nowhere is 'local conditions' addressed regarding windshear and while conditions may be safe for takeoff, we risk violation. Windshear criteria needs to be clarified regarding 'local conditions,' ie, a large hill at the approach end causing turbulence but does not apply to takeoff.

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Original NASA ASRS Text

Title: FLC OF MLG HEARS RPT FROM LNDG MD80 OF A 20 KT LOSS OF AIRSPD. SINCE 15 KTS IS THE LIMIT FOR RPTR ACFT HE REQUESTS OTHER RPTS. TWR INDICATES A LCL CONDITION AND NO RPTS ON TKOF OR CLB. RPTR IS UNSURE OF HIS SIT SINCE 'LCL CONDITION' IS NOT ADDRESSED IN THE REGS.

Narrative: WHILE #1 FOR TKOF, A LNDG MD80 RPTED A 20 KT LOSS OF AIRSPD AT 100 FT. SINCE OVER 15 KTS IS SEVERE WINDSHEAR, I WAS NOT LEGAL FOR TKOF. I ASKED TWR IF THERE WERE ANY ACFT ON APCH FOR A FURTHER RPT. THE ANSWER WAS NO, BUT THAT THE WINDSHEAR WAS DUE TO 'LCL CONDITIONS' AND DID NOT TRANSLATE TO THE OTHER END OF THE FIELD. THIS LEFT ME IN A GRAY AREA, BUT USING MY KNOWLEDGE OF RNO, I MADE THE TKOF. NO WINDSHEAR WAS NOTED ON TKOF OR CLB. NOWHERE IS 'LCL CONDITIONS' ADDRESSED REGARDING WINDSHEAR AND WHILE CONDITIONS MAY BE SAFE FOR TKOF, WE RISK VIOLATION. WINDSHEAR CRITERIA NEEDS TO BE CLARIFIED REGARDING 'LCL CONDITIONS,' IE, A LARGE HILL AT THE APCH END CAUSING TURB BUT DOES NOT APPLY TO TKOF.

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.