Narrative:

We were on a night cross country to bkl with a student. The student preflted the aircraft and checked lights. While looking for traffic overtaking us, I then noticed that our beacon light was not operating. I turned on other lights so that we could be seen. Upon landing at bkl I notified our home base. I was told by the student pilot that he noticed that the beacon was not on. We waited at bkl till the morning so that we could repair the light. Upon returning to osu I found out that the light was inoperative on a previous flight. The chain of events that led up to my noticing the burnt out light started earlier that day. The aircraft should have been downed until the light was changed. Although my student should have caught it, and I should have if he didn't. While I have trust in my student I should have checked all the lights even though my student said everything was working. I am sure that he did check and made a mistake.

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Original NASA ASRS Text

Title: A CFI'S RPT ON ACCEPTING A C172 FOR A NIGHT FLT WITH AN INOP TAIL BEACON LIGHT ON A NIGHT FLT FROM OSU TO BKL, OH.

Narrative: WE WERE ON A NIGHT XCOUNTRY TO BKL WITH A STUDENT. THE STUDENT PREFLTED THE ACFT AND CHKED LIGHTS. WHILE LOOKING FOR TFC OVERTAKING US, I THEN NOTICED THAT OUR BEACON LIGHT WAS NOT OPERATING. I TURNED ON OTHER LIGHTS SO THAT WE COULD BE SEEN. UPON LNDG AT BKL I NOTIFIED OUR HOME BASE. I WAS TOLD BY THE STUDENT PLT THAT HE NOTICED THAT THE BEACON WAS NOT ON. WE WAITED AT BKL TILL THE MORNING SO THAT WE COULD REPAIR THE LIGHT. UPON RETURNING TO OSU I FOUND OUT THAT THE LIGHT WAS INOP ON A PREVIOUS FLT. THE CHAIN OF EVENTS THAT LED UP TO MY NOTICING THE BURNT OUT LIGHT STARTED EARLIER THAT DAY. THE ACFT SHOULD HAVE BEEN DOWNED UNTIL THE LIGHT WAS CHANGED. ALTHOUGH MY STUDENT SHOULD HAVE CAUGHT IT, AND I SHOULD HAVE IF HE DIDN'T. WHILE I HAVE TRUST IN MY STUDENT I SHOULD HAVE CHKED ALL THE LIGHTS EVEN THOUGH MY STUDENT SAID EVERYTHING WAS WORKING. I AM SURE THAT HE DID CHK AND MADE A MISTAKE.

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.