Narrative:

Air carrier X cleared for takeoff runway 9L mia. I heard air carrier Y make some comment re: runway 9L and looked up to see him on short final 9L. I stopped short of 9L and tower asked air carrier Y to land runway 12. He transitioned from about 1/2 mi final to runway 12. Tower said we had been cleared into position runway 12. All 3 of our pilot crew members were positive it was 9L upon subsequent investigation. Mia tower had made the error and had almost caused the accident. The controller was a trnee and the supervisor must not have been closely supervising. This is the second incident in mia in less than 7 days. I've noticed a definite decline in controller competency over the past few yrs. The quality of personnel does not seem to meet past standards. Supplemental information from acn 182629: we were told by tower to taxi into position on runway 9L, the first officer read back, 'roger, position and hold runway 9L' just after crossing the hold short, the captain noticed a small twin lined up to land on 9L at about 1/2 mi. Simultaneously, air carrier Y called tower to ask what was going on. The captain stopped our aircraft just short of the runway. The tower controller then instructed the air carrier Y to land on runway 12 and then accused us of going to the wrong runway.

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Original NASA ASRS Text

Title: CTLR TRAINING IN PROGRESS LCL CTLR TAXIED ACR X ONTO RWY IN FRONT OF ACR Y LNDG.

Narrative: ACR X CLRED FOR TKOF RWY 9L MIA. I HEARD ACR Y MAKE SOME COMMENT RE: RWY 9L AND LOOKED UP TO SEE HIM ON SHORT FINAL 9L. I STOPPED SHORT OF 9L AND TWR ASKED ACR Y TO LAND RWY 12. HE TRANSITIONED FROM ABOUT 1/2 MI FINAL TO RWY 12. TWR SAID WE HAD BEEN CLRED INTO POS RWY 12. ALL 3 OF OUR PLT CREW MEMBERS WERE POSITIVE IT WAS 9L UPON SUBSEQUENT INVESTIGATION. MIA TWR HAD MADE THE ERROR AND HAD ALMOST CAUSED THE ACCIDENT. THE CTLR WAS A TRNEE AND THE SUPVR MUST NOT HAVE BEEN CLOSELY SUPERVISING. THIS IS THE SECOND INCIDENT IN MIA IN LESS THAN 7 DAYS. I'VE NOTICED A DEFINITE DECLINE IN CTLR COMPETENCY OVER THE PAST FEW YRS. THE QUALITY OF PERSONNEL DOES NOT SEEM TO MEET PAST STANDARDS. SUPPLEMENTAL INFO FROM ACN 182629: WE WERE TOLD BY TWR TO TAXI INTO POS ON RWY 9L, THE F/O READ BACK, 'ROGER, POS AND HOLD RWY 9L' JUST AFTER XING THE HOLD SHORT, THE CAPT NOTICED A SMALL TWIN LINED UP TO LAND ON 9L AT ABOUT 1/2 MI. SIMULTANEOUSLY, ACR Y CALLED TWR TO ASK WHAT WAS GOING ON. THE CAPT STOPPED OUR ACFT JUST SHORT OF THE RWY. THE TWR CTLR THEN INSTRUCTED THE ACR Y TO LAND ON RWY 12 AND THEN ACCUSED US OF GOING TO THE WRONG 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.