Narrative:

Aircraft #2 was cleared to land on runway 18R. Aircraft #1 (a foreign carrier) was told to taxi into position on runway 27, (a departure runway only in this confign) and hold, traffic was landing runway 18R. Another aircraft checked in for landing on runway 18R. Upon issuing a wind check I realized that aircraft #1 had a 7 KT tailwind. So I asked if the wind was going to be a problem. He acknowledged with his call sign only for what I thought was receipt of my transmission, when in fact he throttled up and took departure roll. Aircraft #2 was over the numbers on flare. I attempted to cancel the takeoff roll and then proceeded to send aircraft #2 around. By the time aircraft #2 reached the crossing intersection aircraft #2 was approximately 400 ft and aircraft #1 was approximately 200 ft off his right approaching vr. I believe language barrier was the problem. After reviewing the tapes I do not see how my question of the tailwind component was misunderstood for cleared for takeoff. The only thing that possibly could have kept this from happening was due to the language confliction. I could have preceeded my question with, 'aircraft X, continue holding in position runway 27 ...question...' I guess the pilot figured that since he was in position and hold on the runway that my next transmission to him was a takeoff clearance.

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Original NASA ASRS Text

Title: CVG LCL CTLR EXPERIENCED RWY INCIDENT WITH A340 DEP WITHOUT CLRNC.

Narrative: ACFT #2 WAS CLRED TO LAND ON RWY 18R. ACFT #1 (A FOREIGN CARRIER) WAS TOLD TO TAXI INTO POS ON RWY 27, (A DEP RWY ONLY IN THIS CONFIGN) AND HOLD, TFC WAS LNDG RWY 18R. ANOTHER ACFT CHKED IN FOR LNDG ON RWY 18R. UPON ISSUING A WIND CHK I REALIZED THAT ACFT #1 HAD A 7 KT TAILWIND. SO I ASKED IF THE WIND WAS GOING TO BE A PROB. HE ACKNOWLEDGED WITH HIS CALL SIGN ONLY FOR WHAT I THOUGHT WAS RECEIPT OF MY TRANSMISSION, WHEN IN FACT HE THROTTLED UP AND TOOK DEP ROLL. ACFT #2 WAS OVER THE NUMBERS ON FLARE. I ATTEMPTED TO CANCEL THE TKOF ROLL AND THEN PROCEEDED TO SEND ACFT #2 AROUND. BY THE TIME ACFT #2 REACHED THE CROSSING INTERSECTION ACFT #2 WAS APPROX 400 FT AND ACFT #1 WAS APPROX 200 FT OFF HIS R APCHING VR. I BELIEVE LANGUAGE BARRIER WAS THE PROB. AFTER REVIEWING THE TAPES I DO NOT SEE HOW MY QUESTION OF THE TAILWIND COMPONENT WAS MISUNDERSTOOD FOR CLRED FOR TKOF. THE ONLY THING THAT POSSIBLY COULD HAVE KEPT THIS FROM HAPPENING WAS DUE TO THE LANGUAGE CONFLICTION. I COULD HAVE PRECEEDED MY QUESTION WITH, 'ACFT X, CONTINUE HOLDING IN POS RWY 27 ...QUESTION...' I GUESS THE PLT FIGURED THAT SINCE HE WAS IN POS AND HOLD ON THE RWY THAT MY NEXT TRANSMISSION TO HIM WAS A TKOF CLRNC.

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.