Narrative:

While acting as PIC on flight, after departing ord, the tower controller asked us if we had our transponder on. Upon seeing that it was off I said 'no, but it is now' as I turned it on. Apparently, the first officer missed it on the checklist and I failed to notice it before takeoff.

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Original NASA ASRS Text

Title: FLC OF LTT NEGLECTS TO TURN ON XPONDER ON TKOF. TWR QUERIES THEM AND IT IS TURNED ON PROMPTLY.

Narrative: WHILE ACTING AS PIC ON FLT, AFTER DEPARTING ORD, THE TWR CTLR ASKED US IF WE HAD OUR XPONDER ON. UPON SEEING THAT IT WAS OFF I SAID 'NO, BUT IT IS NOW' AS I TURNED IT ON. APPARENTLY, THE FO MISSED IT ON THE CHKLIST AND I FAILED TO NOTICE IT BEFORE 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.