Narrative:

My student and I entered a left crosswind for runway 24 payson which unicom informed us to be the active runway. I heard a plane call 'ready for takeoff, straight out departure'. (I did not hear his north number or aircraft type.) just as we turned to downwind, we were at pattern altitude (6200 ft) just short of midfield when my student suddenly jerked the plane up and to the right. He told me he was sorry for doing that but he had just missed an airplane coming up from in front and to the left. I turned around to see what appeared to be an small aircraft Y filling the back wind screen. I reported over 122.8 (CTAF) that we had just had a near miss with an small aircraft Y that I never heard give a position report. A voice came over the radio stating 'I have been giving position reports and that you had better watch out where you're going'. I am not sure if this was the aircraft who called straight departure as we turned downwind. We called downwind as we turned from crosswind to downwind. We were at recommended pattern altitude approximately 3/4 mi from the runway. The plane was on my blind side. I had no way of seeing it. Thankfully my student did and reacted promptly and correctly. I do not know what he was doing flying the opposite downwind or departing to the left at midfield into opposing traffic. The only thing I could have done (and will do from now on) is to really check my blind side more often at all times. I feel that we entered the traffic pattern correctly at the proper altitudes and distances and made the proper calls.

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Original NASA ASRS Text

Title: NMAC BTWN 2 SMAS IN DEV FROM STANDARD TFC PATTERN PROC.

Narrative: MY STUDENT AND I ENTERED A L XWIND FOR RWY 24 PAYSON WHICH UNICOM INFORMED US TO BE THE ACTIVE RWY. I HEARD A PLANE CALL 'READY FOR TKOF, STRAIGHT OUT DEP'. (I DID NOT HEAR HIS N NUMBER OR ACFT TYPE.) JUST AS WE TURNED TO DOWNWIND, WE WERE AT PATTERN ALT (6200 FT) JUST SHORT OF MIDFIELD WHEN MY STUDENT SUDDENLY JERKED THE PLANE UP AND TO THE R. HE TOLD ME HE WAS SORRY FOR DOING THAT BUT HE HAD JUST MISSED AN AIRPLANE COMING UP FROM IN FRONT AND TO THE L. I TURNED AROUND TO SEE WHAT APPEARED TO BE AN SMA Y FILLING THE BACK WIND SCREEN. I RPTED OVER 122.8 (CTAF) THAT WE HAD JUST HAD A NEAR MISS WITH AN SMA Y THAT I NEVER HEARD GIVE A POS RPT. A VOICE CAME OVER THE RADIO STATING 'I HAVE BEEN GIVING POS RPTS AND THAT YOU HAD BETTER WATCH OUT WHERE YOU'RE GOING'. I AM NOT SURE IF THIS WAS THE ACFT WHO CALLED STRAIGHT DEP AS WE TURNED DOWNWIND. WE CALLED DOWNWIND AS WE TURNED FROM XWIND TO DOWNWIND. WE WERE AT RECOMMENDED PATTERN ALT APPROX 3/4 MI FROM THE RWY. THE PLANE WAS ON MY BLIND SIDE. I HAD NO WAY OF SEEING IT. THANKFULLY MY STUDENT DID AND REACTED PROMPTLY AND CORRECTLY. I DO NOT KNOW WHAT HE WAS DOING FLYING THE OPPOSITE DOWNWIND OR DEPARTING TO THE L AT MIDFIELD INTO OPPOSING TFC. THE ONLY THING I COULD HAVE DONE (AND WILL DO FROM NOW ON) IS TO REALLY CHK MY BLIND SIDE MORE OFTEN AT ALL TIMES. I FEEL THAT WE ENTERED THE TFC PATTERN CORRECTLY AT THE PROPER ALTS AND DISTANCES AND MADE THE PROPER CALLS.

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.