Narrative:

I started a left turn immediately while adding power and noting that this was occurring at 600 ft MSL (400 ft AGL) over a residential area. At the very start of the pull up and turn, we both saw only the left side windows and windscreen of another aircraft turning from right base to final just beneath us. Tower then cleared the other aircraft to land and thanked us for the 360 degree turn. We do not believe the other aircraft ever saw us. It is possible the other aircraft was operating closed pattern for training. They executed a touch-and-go after the incident. Our attention, and that of the tower controller, appears to have been on the departing turbo commander. The aircraft (seneca?) that almost collided with us would have zero relative movement at our 3 O'clock position. We should have been scanning for unexpected traffic while on final, and the tower controller should have been aware of all the aircraft in his pattern. The other aircraft certainly should have called tower on base (as a reminder) and been somewhat vigilant visually and radio-wise.

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Original NASA ASRS Text

Title: DOING A 360 DEG MANEUVER ON SHORT FINAL, A C180 PLT HAS AN NMAC WITH A PIPER SENECA TURNING ON BASE TO FINAL.

Narrative: I STARTED A L TURN IMMEDIATELY WHILE ADDING PWR AND NOTING THAT THIS WAS OCCURRING AT 600 FT MSL (400 FT AGL) OVER A RESIDENTIAL AREA. AT THE VERY START OF THE PULL UP AND TURN, WE BOTH SAW ONLY THE L SIDE WINDOWS AND WINDSCREEN OF ANOTHER ACFT TURNING FROM R BASE TO FINAL JUST BENEATH US. TWR THEN CLRED THE OTHER ACFT TO LAND AND THANKED US FOR THE 360 DEG TURN. WE DO NOT BELIEVE THE OTHER ACFT EVER SAW US. IT IS POSSIBLE THE OTHER ACFT WAS OPERATING CLOSED PATTERN FOR TRAINING. THEY EXECUTED A TOUCH-AND-GO AFTER THE INCIDENT. OUR ATTN, AND THAT OF THE TWR CTLR, APPEARS TO HAVE BEEN ON THE DEPARTING TURBO COMMANDER. THE ACFT (SENECA?) THAT ALMOST COLLIDED WITH US WOULD HAVE ZERO RELATIVE MOVEMENT AT OUR 3 O'CLOCK POS. WE SHOULD HAVE BEEN SCANNING FOR UNEXPECTED TFC WHILE ON FINAL, AND THE TWR CTLR SHOULD HAVE BEEN AWARE OF ALL THE ACFT IN HIS PATTERN. THE OTHER ACFT CERTAINLY SHOULD HAVE CALLED TWR ON BASE (AS A REMINDER) AND BEEN SOMEWHAT VIGILANT VISUALLY AND RADIO-WISE.

Data retrieved from NASA's ASRS site as of July 2007 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.