Narrative:

While taxiing onto the active runway I asked the tower for the approach control frequency for departure. I put the frequency on the same radio I had the tower frequency on. I took off and hadn't realized my mistake until I went to change frequency. I may have taken off without clearance. In effect, I took off with departure control frequency on my radio without realizing it. Suggest aircraft not be cleared onto runway unless cleared for takeoff.

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Original NASA ASRS Text

Title: TKOF WITHOUT A CLRNC.

Narrative: WHILE TAXIING ONTO THE ACTIVE RWY I ASKED THE TWR FOR THE APCH CTL FREQ FOR DEP. I PUT THE FREQ ON THE SAME RADIO I HAD THE TWR FREQ ON. I TOOK OFF AND HADN'T REALIZED MY MISTAKE UNTIL I WENT TO CHANGE FREQ. I MAY HAVE TAKEN OFF WITHOUT CLRNC. IN EFFECT, I TOOK OFF WITH DEP CTL FREQ ON MY RADIO WITHOUT REALIZING IT. SUGGEST ACFT NOT BE CLRED ONTO RWY UNLESS CLRED FOR TKOF.

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.