Narrative:

I called ffz tower from the north. I was instructed to enter a left downwind for runway 4L. I called the 45 degree entry to the left downwind 'over the river.' I heard tower tell the low wing single engine aircraft to extend his pattern to follow me. Abeam the approach end of the runway at 'the number' tower told me to extend downwind for a C-210 landing. I told the tower; I would extend plus slow. Almost immediately tower cleared me to land 'the 210 is over the numbers runway 4L'. I pulled power to idle and began to slow the airplane to turn left base. A new student was in the left seat receiving private pilot instruction. I was demonstrating the landing from the right seat. I had just begun a descent when the student told me there was an airplane to my left. I looked to my left and saw the landing gear of the low wing single engine aircraft that was told to follow me just to the left of my left wing. I have been in aircraft flying formation; this airplane was as close as a close formation flight -- within a wingspan distance. I pushed forward on the yoke to descend beneath the airplane. At the same time I called tower and advised him of my intentions. The tower operator began to issue instructions to the pilot of the low wing single engine aircraft. The pilot of the low wing single engine aircraft did not respond/seemed confused. I don't believe he ever saw my airplane. After some instructions to the other pilot from the tower to turn left and head north or something close to that that tower told me to extend my downwind. At this time I realized the tower had confused the 2 airplanes. I told the tower I was the airplane on base. The tower then told us cleared to land. I landed on runway 4L safely.

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Original NASA ASRS Text

Title: A pilot giving instructions during a visual approach to FFZ Runway 4L had a NMAC with another aircraft which had not followed ATC instructions to follow the reporter.

Narrative: I called FFZ Tower from the north. I was instructed to enter a left downwind for Runway 4L. I called the 45 degree entry to the left downwind 'over the river.' I heard Tower tell the low wing single engine aircraft to extend his pattern to follow me. Abeam the approach end of the runway at 'the number' Tower told me to extend downwind for a C-210 landing. I told the Tower; I would extend plus slow. Almost immediately Tower cleared me to land 'the 210 is over the numbers Runway 4L'. I pulled power to idle and began to slow the airplane to turn left base. A new student was in the left seat receiving private pilot instruction. I was demonstrating the landing from the right seat. I had just begun a descent when the student told me there was an airplane to my left. I looked to my left and saw the landing gear of the low wing single engine aircraft that was told to follow me just to the left of my left wing. I have been in aircraft flying formation; this airplane was as close as a close formation flight -- within a wingspan distance. I pushed forward on the yoke to descend beneath the airplane. At the same time I called Tower and advised him of my intentions. The Tower Operator began to issue instructions to the pilot of the low wing single engine aircraft. The pilot of the low wing single engine aircraft did not respond/seemed confused. I don't believe he ever saw my airplane. After some instructions to the other pilot from the Tower to turn left and head north or something close to that that Tower told me to extend my downwind. At this time I realized the Tower had confused the 2 airplanes. I told the Tower I was the airplane on base. The Tower then told us cleared to land. I landed on Runway 4L safely.

Data retrieved from NASA's ASRS site as of April 2012 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.