Narrative:

We were descending into cvg in light to moderate rain and at that point were no where near any returns on the radar. When we were handed off to approach the controller told us 'turn left 170 to avoid weather; vectors runway 27'; I didn't know what weather he was talking about but the heading he gave us was about the same as what we were in at the moment so we accepted the turn. About the time we leveled out in the turn there was a loud bang on the right side of the airplane as a lightning bolt struck in close proximity. There were no fluctuations in any indications and the flight continued normally. When we landed in cvg I did the post flight inspection and informed the company mechanic we had lightning in the proximity of the airplane and to look it over. Neither the mechanic nor I saw any indications of a lightning strike; so we continued on our trip. I elected not to make a logbook entry as directed by our company fom because I did not think we had been struck. I received a call this morning advising that maintenance had found a lightning strike and the airplane would require repairs and an inspection. The damage was on the top side of the right aileron; and was invisible from both the ground and the flight deck. This find was made after the airplane had flown for six legs after the fact; five of those were flown by my same crew. At no time on the subsequent legs did I see any evidence leading me to believe it was a lightning strike. The only thing I would have done different is I would have placed an entry in the log book and had maintenance do a more thorough inspection.

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Original NASA ASRS Text

Title: Damage inflicted to the right upper aileron of a B757-200 went undetected for several flights until discovered by maintenance personnel.

Narrative: We were descending into CVG in light to moderate rain and at that point were no where near any returns on the radar. When we were handed off to Approach the Controller told us 'turn left 170 to avoid weather; vectors Runway 27'; I didn't know what weather he was talking about but the heading he gave us was about the same as what we were in at the moment so we accepted the turn. About the time we leveled out in the turn there was a loud bang on the right side of the airplane as a lightning bolt struck in close proximity. There were no fluctuations in any indications and the flight continued normally. When we landed in CVG I did the post flight inspection and informed the company mechanic we had lightning in the proximity of the airplane and to look it over. Neither the mechanic nor I saw any indications of a lightning strike; so we continued on our trip. I elected not to make a logbook entry as directed by our company FOM because I did not think we had been struck. I received a call this morning advising that maintenance had found a lightning strike and the airplane would require repairs and an inspection. The damage was on the top side of the right aileron; and was invisible from both the ground and the flight deck. This find was made after the airplane had flown for six legs after the fact; five of those were flown by my same crew. At no time on the subsequent legs did I see any evidence leading me to believe it was a lightning strike. The only thing I would have done different is I would have placed an entry in the log book and had maintenance do a more thorough inspection.

Data retrieved from NASA's ASRS site as of April 2012 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.