Narrative:

I was on extended downwind; right traffic for runway xx; approximately 3.5 miles south of the runway. Controller had told me he would call my base. It was a busy pattern. I heard him clear another aircraft further south of my position for landing xx; traffic ahead was a cessna on 3 and a half mile final. The other aircraft said they had no traffic in sight. Controller asked me if I was on final. I responded; 'negative; you didn't call my base.' controller responded: 'cessna 182 turn left to north heading; fly to the highway; then re-enter right pattern at midfield.' I confirmed the instruction; then turned left to a north heading and started flying to the highway. Within 10-30 seconds; I saw oncoming traffic; another cessna flying directly toward me at what seemed to be a very similar altitude. I veered to the right; but noticed oncoming traffic did not veer right. I immediately called: 'tower; cessna 182 almost collided with another aircraft.' I don't recall my exact words; I was very flustered at the time. When my radio transmission ended; I heard the other aircraft calling tower asking if they had mistakenly flown their course too wide. It appeared my transmission had been 'stepped on.' controller asked my position. He then gave me the same instruction as before; to fly to [the highway]; then re-enter the right downwind at midfield. I did that; and this time was able to land with no issue. This is a great airspace to fly in. The controllers are always courteous; and even forgiving. This is the first time I have been in a situation as PIC that made me feel uncomfortable flying in their airspace. I didn't recognize the controller's voice. I don't want to cause trouble for anyone; just want to make sure this kind of thing can be prevented in the future.

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Original NASA ASRS Text

Title: VFR pattern traffic instructed to re-enter the downwind experienced a NMAC with other traffic entering the pattern.

Narrative: I was on extended downwind; right traffic for Runway XX; approximately 3.5 miles south of the runway. Controller had told me he would call my base. It was a busy pattern. I heard him clear another aircraft further south of my position for landing XX; traffic ahead was a Cessna on 3 and a half mile final. The other aircraft said they had no traffic in sight. Controller asked me if I was on final. I responded; 'Negative; you didn't call my base.' Controller responded: 'Cessna 182 turn left to north heading; fly to the highway; then re-enter right pattern at midfield.' I confirmed the instruction; then turned left to a north heading and started flying to the highway. Within 10-30 seconds; I saw oncoming traffic; another Cessna flying directly toward me at what seemed to be a very similar altitude. I veered to the right; but noticed oncoming traffic did not veer right. I immediately called: 'Tower; Cessna 182 almost collided with another aircraft.' I don't recall my exact words; I was very flustered at the time. When my radio transmission ended; I heard the other aircraft calling Tower asking if they had mistakenly flown their course too wide. It appeared my transmission had been 'stepped on.' Controller asked my position. He then gave me the same instruction as before; to fly to [the highway]; then re-enter the right downwind at midfield. I did that; and this time was able to land with no issue. This is a great airspace to fly in. The controllers are always courteous; and even forgiving. This is the first time I have been in a situation as PIC that made me feel uncomfortable flying in their airspace. I didn't recognize the Controller's voice. I don't want to cause trouble for anyone; just want to make sure this kind of thing can be prevented in the future.

Data retrieved from NASA's ASRS site as of July 2013 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.