Narrative:

As I was returning from a recreational flight from the south of john wayne airport; socal on frequency 124.1 advised me to proceed direct to signal peak for the normal VFR pattern entry to john wayne airport. I was handed off to the john wayne tower on frequency 119.9 and told to make left traffic for runway 20L. While downwind; I was cleared to land on runway 20L and cautioned for wake turbulence from a 737 that was making a go around on runway 20R. As I proceeded downwind at around 100-110 kts with 50% flaps; I began a normal pattern descent and began my base turn. I was just starting my base to final turn; between 90 to 100 knots and around 700 feet MSL (I was above 500 feet because my terrain warning of 500 feet had not yet sounded); when I saw a cessna (believe it was a cessna 172) coming straight toward me from the pilot's side window. The cessna was flying a pattern inside of me. It appeared to be flying a downwind pattern; and was on a collision course with my base turning cirrus. I steepened my angle of descent; and dove away from the cessna. It passed immediately behind my tail. I did not have any time to observe the cessna after I initially saw it and took evasive action. I estimate it passed close behind my tail at my same altitude.I continued my descent and transitioned from base to final and landed without event on runway 20L. While on short final; I reported this near miss to the tower controller. The controller confirmed I was number one and cleared to land; and that the cessna was to follow me.

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Original NASA ASRS Text

Title: An SR22 pilot reported an NMAC in the pattern at SNA.

Narrative: As I was returning from a recreational flight from the south of John Wayne Airport; SoCal on frequency 124.1 advised me to proceed direct to Signal Peak for the normal VFR pattern entry to John Wayne Airport. I was handed off to the John Wayne Tower on frequency 119.9 and told to make left traffic for Runway 20L. While downwind; I was cleared to land on Runway 20L and cautioned for wake turbulence from a 737 that was making a go around on Runway 20R. As I proceeded downwind at around 100-110 kts with 50% flaps; I began a normal pattern descent and began my base turn. I was just starting my base to final turn; between 90 to 100 knots and around 700 feet MSL (I was above 500 feet because my terrain warning of 500 feet had not yet sounded); when I saw a Cessna (believe it was a Cessna 172) coming straight toward me from the pilot's side window. The Cessna was flying a pattern inside of me. It appeared to be flying a downwind pattern; and was on a collision course with my base turning Cirrus. I steepened my angle of descent; and dove away from the Cessna. It passed immediately behind my tail. I did not have any time to observe the Cessna after I initially saw it and took evasive action. I estimate it passed close behind my tail at my same altitude.I continued my descent and transitioned from base to final and landed without event on Runway 20L. While on short final; I reported this near miss to the tower controller. The controller confirmed I was number one and cleared to land; and that the Cessna was to follow me.

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.