Narrative:

Told tower that I was ready for takeoff on runway 9L but I was really ready for takeoff on runway 9R. Tower cleared me for takeoff runway 9L. When I was on takeoff roll I noticed that I had been calling ready for runway 9L and was on runway 9R. To prevent this from happening again or being a recurrence is to be aware of what is being said to tower and what you are reading.

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Original NASA ASRS Text

Title: A MOONEY 20J CFI PERFORMS A TKOF ON RWY 9R WHEN CLRED FOR TKOF BY TWR ON RWY 9L AT FCM, MN.

Narrative: TOLD TWR THAT I WAS READY FOR TKOF ON RWY 9L BUT I WAS REALLY READY FOR TKOF ON RWY 9R. TWR CLRED ME FOR TKOF RWY 9L. WHEN I WAS ON TKOF ROLL I NOTICED THAT I HAD BEEN CALLING READY FOR RWY 9L AND WAS ON RWY 9R. TO PREVENT THIS FROM HAPPENING AGAIN OR BEING A RECURRENCE IS TO BE AWARE OF WHAT IS BEING SAID TO TWR AND WHAT YOU ARE READING.

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.