Narrative:

For the entire flight we had ATC 'flight following' and a squawk transponder code. Approximately 11 miles from vll; detroit approach terminated our radar coverage. They said there was only a single aircraft between us and the airport; who was likely just taking off from vll. They then warned us of numerous aircraft in the area due to the 'woodward dream cruise' event. At approximately 5 miles to the west of vll; with the dream cruise between us and the airport; we heard aircraft Y announce his position and intent to land at vll. He was approximately 5 miles to the north; intending to overfly the airport and enter a left downwind for runway 27.I announced our position as being 5 miles to the west; also intending to enter the left downwind to runway 27. Soon after I saw a small aircraft passing us to the north with a banner attached. I thought that this was the aircraft detroit approach warned us about. Therefor I continued to look for aircraft Y who was approaching us from my left and heading for a similar entry point for runway 27. I think I announced my position at least 2 miles from the airport; then again upon entering the downwind for 27. It was right after this transmission a blue high wing cessna passed in front of me towing a banner.I immediately dove and turned right. While I cannot say for certain how close we were to each other; I feel like we were within 500 feet at approximately the same altitude. (The cessna was slightly higher than me; but the banner was hanging lower than my plane) there was no contact made between either plane and I was able to continue my approach and land without incident.after further reflection of the situation; I feel that there were several things that could have been done to prevent this incident.1. A NOTAM could have been published advising all aircraft of the risks involved; due to the numerous banner towing planes flying in the area west of vll during the 'woodward dream cruise.' woodward avenue is a major north / south road which is only about one(1) mile from the west end of vll. Approximately one(1) million people attend this annual event.2. Detroit approach could have vectored me to the north of the 'woodward dream cruise' in order to avoid the area of highest risk; due to the multiple banner towing planes in the area who were operating at traffic pattern altitude.3. The banner towing planes; who were operating out of vll; should have been monitoring the vll unicom frequency and have announced their position. This would have made me aware of their location and prevented this incident.4. The banner towing activity should not have been performed at 'pattern altitude' within 1 mile of the airport. I feel like they should have been overflying the airport at least 500 feet above pattern altitude.5. I could have briefed my passengers to be looking for other aircraft in the area and advise me if anything was noticed.6. Being a local resident; but unfortunately a relatively new pilot; I should have been aware of the risks associated with the 'woodward dream cruise' and have planned a route which would have minimized this risk.

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Original NASA ASRS Text

Title: Pilot reported a NMAC with a NORDO banner tow aircraft while entering pattern.

Narrative: For the entire flight we had ATC 'flight following' and a squawk transponder code. Approximately 11 miles from VLL; Detroit Approach terminated our radar coverage. They said there was only a single aircraft between us and the airport; who was likely just taking off from VLL. They then warned us of numerous aircraft in the area due to the 'Woodward Dream Cruise' event. At approximately 5 miles to the west of VLL; with the Dream Cruise between us and the airport; we heard Aircraft Y announce his position and intent to land at VLL. He was approximately 5 miles to the north; intending to overfly the airport and enter a left downwind for Runway 27.I announced our position as being 5 miles to the west; also intending to enter the left downwind to Runway 27. Soon after I saw a small aircraft passing us to the north with a banner attached. I thought that this was the aircraft Detroit Approach warned us about. Therefor I continued to look for Aircraft Y who was approaching us from my left and heading for a similar entry point for Runway 27. I think I announced my position at least 2 miles from the airport; then again upon entering the downwind for 27. It was right after this transmission a blue high wing Cessna passed in front of me towing a banner.I immediately dove and turned right. While I cannot say for certain how close we were to each other; I feel like we were within 500 feet at approximately the same altitude. (The Cessna was slightly higher than me; but the banner was hanging lower than my plane) There was no contact made between either plane and I was able to continue my approach and land without incident.After further reflection of the situation; I feel that there were several things that could have been done to prevent this incident.1. A NOTAM could have been published advising all aircraft of the risks involved; due to the numerous Banner towing planes flying in the area west of VLL during the 'Woodward Dream Cruise.' Woodward Avenue is a major north / south road which is only about One(1) mile from the west end of VLL. Approximately One(1) million people attend this annual event.2. Detroit Approach could have vectored me to the north of the 'Woodward Dream Cruise' in order to avoid the area of highest risk; due to the multiple banner towing planes in the area who were operating at traffic pattern altitude.3. The Banner towing planes; who were operating out of VLL; should have been monitoring the VLL UNICOM frequency and have announced their position. This would have made me aware of their location and prevented this incident.4. The Banner towing activity should not have been performed at 'Pattern Altitude' within 1 mile of the airport. I feel like they should have been overflying the airport at least 500 feet above pattern altitude.5. I could have briefed my passengers to be looking for other aircraft in the area and advise me if anything was noticed.6. Being a local resident; but unfortunately a relatively new pilot; I should have been aware of the risks associated with the 'Woodward Dream Cruise' and have planned a route which would have minimized this risk.

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.