Narrative:

Flight was cleared from gate to runway 27L mia via ramp. Signs at the end of ramp where runway 27L and 30 merge led me to believe I was approaching end of runway 27L. In reality, I had crossed over 27L and was starting rolling takeoff on runway 30. As we rolled onto runway 30, the error was immediately apparent and takeoff stopped. Tower was informed and we were told to back-track on runway 30. And we were cleared for takeoff on that runway (30). Our airspeed was probably about 15 KTS when stop was made. We had gone down runway 30 about 100-150 ft. I suspect we were not the first to make this mistake. I suggest runway signs be made clrer when runways merge as they do at miami's runways 27L and 30.

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Original NASA ASRS Text

Title: AN ACR LGT PLT ABORTED HIS TKOF WHEN HE REALIZED THAT HE WAS ON THE WRONG RWY.

Narrative: FLT WAS CLRED FROM GATE TO RWY 27L MIA VIA RAMP. SIGNS AT THE END OF RAMP WHERE RWY 27L AND 30 MERGE LED ME TO BELIEVE I WAS APCHING END OF RWY 27L. IN REALITY, I HAD CROSSED OVER 27L AND WAS STARTING ROLLING TKOF ON RWY 30. AS WE ROLLED ONTO RWY 30, THE ERROR WAS IMMEDIATELY APPARENT AND TKOF STOPPED. TWR WAS INFORMED AND WE WERE TOLD TO BACK-TRACK ON RWY 30. AND WE WERE CLRED FOR TKOF ON THAT RWY (30). OUR AIRSPD WAS PROBABLY ABOUT 15 KTS WHEN STOP WAS MADE. WE HAD GONE DOWN RWY 30 ABOUT 100-150 FT. I SUSPECT WE WERE NOT THE FIRST TO MAKE THIS MISTAKE. I SUGGEST RWY SIGNS BE MADE CLRER WHEN RWYS MERGE AS THEY DO AT MIAMI'S RWYS 27L AND 30.

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.