Narrative:

Towing banner; getting a northbound transition with [ATC]. [ATC] did not advise of any traffic. When approaching [a local landmark]; I see the back end of a blimp off my right wing. I immediately descended to avoid collision.

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Original NASA ASRS Text

Title: A banner tow pilot reported an NMAC with a blimp not called out by ATC while transitioning through their airspace.

Narrative: Towing banner; getting a northbound transition with [ATC]. [ATC] did not advise of any traffic. When approaching [a local landmark]; I see the back end of a blimp off my right wing. I immediately descended to avoid collision.

Data retrieved from NASA's ASRS site 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.