Narrative:

When cleared for takeoff on runway 27L by miami international tower, a brief moment of confusion existed in the cockpit as to our exact location on the airfield. The taxi flow was being fed into 27L and 30. When our flight was cleared for takeoff, the captain and myself briefly doubted whether we were in fact turning onto runway 27L. The point of confusion was a yellow taxi sign just inside of the taxi line onto the runway. This sign was directly adjacent to 27L. Not wanting to takeoff on a runway not cleared for, we taxiied over what was actually 27L to an area between 27L and 30. At this point tower asked if we still wanted 27L or 30, having cleared us for takeoff on 27L. We were now pretty sure 27L was behind us and after discussing our options with tower we received clearance and took off from 30. Although this was during a morning bank of departures, no undue delay for our departure or other departures or arrs resulted. The tower controller had control of the situation throughout. In retrospect, we were where we thought we were on the airport but were confused by the yellow taxi sign (intended to point to 30/12 ?) although this is not our normal hub, we should be able to operate there with no confusion. This obviously was a lesson learned for us and there was no harm done. I do feel that a potential exists for having an aircraft roll on the wrong runway.

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Original NASA ASRS Text

Title: FLC BECAME CONFUSED WHILE TAXIING TO RWY 27L AT MIA AND STARTED TO POS THEMSELVES FOR TKOF ON RWY 30.

Narrative: WHEN CLRED FOR TKOF ON RWY 27L BY MIAMI INTL TWR, A BRIEF MOMENT OF CONFUSION EXISTED IN THE COCKPIT AS TO OUR EXACT LOCATION ON THE AIRFIELD. THE TAXI FLOW WAS BEING FED INTO 27L AND 30. WHEN OUR FLT WAS CLRED FOR TKOF, THE CAPT AND MYSELF BRIEFLY DOUBTED WHETHER WE WERE IN FACT TURNING ONTO RWY 27L. THE POINT OF CONFUSION WAS A YELLOW TAXI SIGN JUST INSIDE OF THE TAXI LINE ONTO THE RWY. THIS SIGN WAS DIRECTLY ADJACENT TO 27L. NOT WANTING TO TKOF ON A RWY NOT CLRED FOR, WE TAXIIED OVER WHAT WAS ACTUALLY 27L TO AN AREA BTWN 27L AND 30. AT THIS POINT TWR ASKED IF WE STILL WANTED 27L OR 30, HAVING CLRED US FOR TKOF ON 27L. WE WERE NOW PRETTY SURE 27L WAS BEHIND US AND AFTER DISCUSSING OUR OPTIONS WITH TWR WE RECEIVED CLRNC AND TOOK OFF FROM 30. ALTHOUGH THIS WAS DURING A MORNING BANK OF DEPS, NO UNDUE DELAY FOR OUR DEP OR OTHER DEPS OR ARRS RESULTED. THE TWR CTLR HAD CTL OF THE SITUATION THROUGHOUT. IN RETROSPECT, WE WERE WHERE WE THOUGHT WE WERE ON THE ARPT BUT WERE CONFUSED BY THE YELLOW TAXI SIGN (INTENDED TO POINT TO 30/12 ?) ALTHOUGH THIS IS NOT OUR NORMAL HUB, WE SHOULD BE ABLE TO OPERATE THERE WITH NO CONFUSION. THIS OBVIOUSLY WAS A LESSON LEARNED FOR US AND THERE WAS NO HARM DONE. I DO FEEL THAT A POTENTIAL EXISTS FOR HAVING AN ACFT ROLL ON 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.