Narrative:

Tower cleared us into position and hold on runway 5L. I released brakes and started to advance and checked final approach. I observed an aircraft on short final (3 mi?) but couldn't tell at this point whether it was lined up on runway 5L or runway 5R because they are so close together. I stopped the aircraft short of the runway and continued to watch the aircraft. It soon became apparent the aircraft, an A320, was lined up on runway 5L. We watched the aircraft pass by and execute a low approach approximately 20 ft AGL some ways down the runway, due to the displaced threshold. The first officer then asked tower why he had cleared us into position with an aircraft on short final. Tower was amazingly non-chalant and replied 'ok, now you can taxi into position and hold.' the rest of the flight was uneventful. One large problem here is the use of spanish on ATC frequencys. It makes it very difficult to monitor the situation. Supplemental information from acn 622298: as most of the communications were taking place in spanish, I have no idea if the aircraft was told to go around or if the go around was accomplished by the pilot in reference to our aircraft which was not on the runway.

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Original NASA ASRS Text

Title: B737 CREW WAS CLRED INTO POS AND HOLD IN FRONT OF A LNDG ACFT AT MMMX.

Narrative: TWR CLRED US INTO POS AND HOLD ON RWY 5L. I RELEASED BRAKES AND STARTED TO ADVANCE AND CHKED FINAL APCH. I OBSERVED AN ACFT ON SHORT FINAL (3 MI?) BUT COULDN'T TELL AT THIS POINT WHETHER IT WAS LINED UP ON RWY 5L OR RWY 5R BECAUSE THEY ARE SO CLOSE TOGETHER. I STOPPED THE ACFT SHORT OF THE RWY AND CONTINUED TO WATCH THE ACFT. IT SOON BECAME APPARENT THE ACFT, AN A320, WAS LINED UP ON RWY 5L. WE WATCHED THE ACFT PASS BY AND EXECUTE A LOW APCH APPROX 20 FT AGL SOME WAYS DOWN THE RWY, DUE TO THE DISPLACED THRESHOLD. THE FO THEN ASKED TWR WHY HE HAD CLRED US INTO POS WITH AN ACFT ON SHORT FINAL. TWR WAS AMAZINGLY NON-CHALANT AND REPLIED 'OK, NOW YOU CAN TAXI INTO POS AND HOLD.' THE REST OF THE FLT WAS UNEVENTFUL. ONE LARGE PROB HERE IS THE USE OF SPANISH ON ATC FREQS. IT MAKES IT VERY DIFFICULT TO MONITOR THE SIT. SUPPLEMENTAL INFO FROM ACN 622298: AS MOST OF THE COMS WERE TAKING PLACE IN SPANISH, I HAVE NO IDEA IF THE ACFT WAS TOLD TO GO AROUND OR IF THE GAR WAS ACCOMPLISHED BY THE PLT IN REF TO OUR ACFT WHICH WAS NOT ON THE RWY.

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.