Narrative:

I am a flight instructor coming back from a training flight. Airport was extremely busy and was taken out to a 5 mi base turn. Once on a 3/4 mi final at smo I was instructed by tower to turn right; climb and enter in a north downwind. Once at 500 ft AGL I began a right turn. Right before I started my climb in a single engine plane (probably a cessna) that was white with a blue color scheme flies over my plane from behind and above who was descending and turning from a north base onto final. I began a right turn but hesitated to climb due to the other plane being above me and descending. Once the plane was no longer in front of me; I started a climb to re-enter on a north downwind and land normally.

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Original NASA ASRS Text

Title: VFR C172 STRAIGHT IN ARR TO SMO EXPERIENCED NMAC AFTER TWR INSTRUCTED HIM/HER TO CLIMB AND MAKE DOWNWIND ENTRY.

Narrative: I AM A FLT INSTRUCTOR COMING BACK FROM A TRAINING FLT. ARPT WAS EXTREMELY BUSY AND WAS TAKEN OUT TO A 5 MI BASE TURN. ONCE ON A 3/4 MI FINAL AT SMO I WAS INSTRUCTED BY TWR TO TURN R; CLB AND ENTER IN A N DOWNWIND. ONCE AT 500 FT AGL I BEGAN A R TURN. R BEFORE I STARTED MY CLB IN A SINGLE ENG PLANE (PROBABLY A CESSNA) THAT WAS WHITE WITH A BLUE COLOR SCHEME FLIES OVER MY PLANE FROM BEHIND AND ABOVE WHO WAS DSNDING AND TURNING FROM A N BASE ONTO FINAL. I BEGAN A R TURN BUT HESITATED TO CLB DUE TO THE OTHER PLANE BEING ABOVE ME AND DSNDING. ONCE THE PLANE WAS NO LONGER IN FRONT OF ME; I STARTED A CLB TO RE-ENTER ON A N DOWNWIND AND LAND NORMALLY.

Data retrieved from NASA's ASRS site as of May 2009 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.