Narrative:

After engine start we were cleared to taxi to runway 27L. (This is very short taxi from gate xx to runway 27L.) while running the after start and taxi checklist, the captain taxied onto runway 27L from taxiway Q. I stated to the captain that 'you're taxiing onto the active runway.' his response was 'no we're not!' shortly, mia tower called 'air carrier X, I see you're ready for takeoff.' I advanced the throttles for takeoff and started the roll down runway 27L. The captain started to turn the aircraft to the right onto runway 30. I stated that 'we're on the takeoff runway.' he straightened the aircraft down runway 27L and the takeoff was normal.

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Original NASA ASRS Text

Title: CAPT OF A WDB FAILED TO HOLD SHORT OF RWY AND INADVERTENTLY TAXIED ONTO THE ACTIVE CAUSING THE FO, WHO WAS RUNNING THE CHKLIST, TO INFORM THE CAPT OF HIS MISTAKE. THE CAPT DID NOT BELIEVE THAT HE HAD UNTIL THE TWR ADVISED AND PROVIDED TKOF CLRNC.

Narrative: AFTER ENG START WE WERE CLRED TO TAXI TO RWY 27L. (THIS IS VERY SHORT TAXI FROM GATE XX TO RWY 27L.) WHILE RUNNING THE AFTER START AND TAXI CHKLIST, THE CAPT TAXIED ONTO RWY 27L FROM TXWY Q. I STATED TO THE CAPT THAT 'YOU'RE TAXIING ONTO THE ACTIVE RWY.' HIS RESPONSE WAS 'NO WE'RE NOT!' SHORTLY, MIA TWR CALLED 'ACR X, I SEE YOU'RE READY FOR TKOF.' I ADVANCED THE THROTTLES FOR TKOF AND STARTED THE ROLL DOWN RWY 27L. THE CAPT STARTED TO TURN THE ACFT TO THE R ONTO RWY 30. I STATED THAT 'WE'RE ON THE TKOF RWY.' HE STRAIGHTENED THE ACFT DOWN RWY 27L AND THE TKOF WAS NORMAL.

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.