Narrative:

I was working the local and ground control positions combined. The fog conditions were such that I could not see and ground or airborne operations on or about the airport. During these conditions a controller must rely solely on PIREPS. Xx called me for a pushback from the gate. I instructed the pilot to plan runway 1L for a departure and issued the RVR. When called to taxi, I issued specific taxi route instructions to runway 1L. The pilot read back the instructions verbatim. When xx called ready for departure, I cleared the aircraft for takeoff on runway 1L. I could only hear the aircraft depart; I could not see it, but it was very evident from the radar display that the aircraft had departed runway 7R. It was shear luck that no other aircraft or vehicles were crossing this runway at the time.

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Original NASA ASRS Text

Title: FLT CREW OF MLG REPORTEDLY TOOK OFF ON WRONG RWY AT MKE IN HEAVY FOG. REDUCED VISIBILITY--TWR COULD ONLY MONITOR ON BRITE.

Narrative: I WAS WORKING THE LCL AND GND CTL POSITIONS COMBINED. THE FOG CONDITIONS WERE SUCH THAT I COULD NOT SEE AND GND OR AIRBORNE OPS ON OR ABOUT THE ARPT. DURING THESE CONDITIONS A CTLR MUST RELY SOLELY ON PIREPS. XX CALLED ME FOR A PUSHBACK FROM THE GATE. I INSTRUCTED THE PLT TO PLAN RWY 1L FOR A DEP AND ISSUED THE RVR. WHEN CALLED TO TAXI, I ISSUED SPECIFIC TAXI RTE INSTRUCTIONS TO RWY 1L. THE PLT READ BACK THE INSTRUCTIONS VERBATIM. WHEN XX CALLED READY FOR DEP, I CLRED THE ACFT FOR TKOF ON RWY 1L. I COULD ONLY HEAR THE ACFT DEPART; I COULD NOT SEE IT, BUT IT WAS VERY EVIDENT FROM THE RADAR DISPLAY THAT THE ACFT HAD DEPARTED RWY 7R. IT WAS SHEAR LUCK THAT NO OTHER ACFT OR VEHICLES WERE XING THIS RWY AT THE TIME.

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.