Narrative:

All the windows in the tower cabin attendant were foggy. An heavy transport X was instructed to change landing runway from runway 30 to runway 27L, the aircraft lined up for 27R. An air carrier large transport Y was in position on runway 27R on another frequency thus not aware of the situation. The heavy transport was not visible from the tower due to the condensation on the windows. At the last possible min the heavy transport was sent around avoiding a possible collision. The heavy transport evidently did not see the large transport in position. This needs to be fixed as soon as possible before loss of life, then the FAA will have no choice.

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Original NASA ASRS Text

Title: ACR ON FINAL MAKES APCH TO WRONG RWY AND GOES AROUND AT LAST MIN. CTLR COULD NOT SEE DUE TO TWR WINDOWS BEING FOGGED UP.

Narrative: ALL THE WINDOWS IN THE TWR CAB WERE FOGGY. AN HVT X WAS INSTRUCTED TO CHANGE LNDG RWY FROM RWY 30 TO RWY 27L, THE ACFT LINED UP FOR 27R. AN ACR LGT Y WAS IN POS ON RWY 27R ON ANOTHER FREQ THUS NOT AWARE OF THE SITUATION. THE HVT WAS NOT VISIBLE FROM THE TWR DUE TO THE CONDENSATION ON THE WINDOWS. AT THE LAST POSSIBLE MIN THE HVT WAS SENT AROUND AVOIDING A POSSIBLE COLLISION. THE HVT EVIDENTLY DID NOT SEE THE LGT IN POS. THIS NEEDS TO BE FIXED ASAP BEFORE LOSS OF LIFE, THEN THE FAA WILL HAVE NO CHOICE.

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.