Narrative:

When my student and I (in small aircraft X) turned base (for 24L), we heard someone call 'downwind 24' west/O saying left or right. I questioned the other aircraft about left or right runway, and he replied 'downwind 24.' I could tell by his voice that he was confused, so I explained which runway was which (by telling him the right runway was white concrete and the left one was black top) and explained the pattern direction for both runways. At the end of the transmission I reported turning a 3/4 mi final. The other aircraft (an small aircraft Y) reported downwind for 24R. My student and I looked for the other aircraft in the pattern for 24R,but could not see him. We also raised both wings and looked through the skylights to see if he was near us. We were landing using a short field procedure, did a good T/D on the #'south, and I applied the power slowly to start a takeoff. As the engine started to accelerate, small aircraft Y flashed in front of us. We locked up the brakes and avoided the contact. After landing I talked to the student in the other aircraft and drew the patterns for the runways on his clipboard. He was only in the pattern once before and didn't have permission from his instrument to land at our airport. I talked to the instrument later on the phone, and the student was informed of the rules. He just forgot. The student had been in a left downwind for 24R, when a right pattern is required.

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Original NASA ASRS Text

Title: STUDENT PLT FLYING SOLO BECOMES CONFUSED IN PATTERN AT NON TWR ARPT AND LANDS OVER TOP OF SMA ON TOUCH AND GO.

Narrative: WHEN MY STUDENT AND I (IN SMA X) TURNED BASE (FOR 24L), WE HEARD SOMEONE CALL 'DOWNWIND 24' W/O SAYING LEFT OR RIGHT. I QUESTIONED THE OTHER ACFT ABOUT LEFT OR RIGHT RWY, AND HE REPLIED 'DOWNWIND 24.' I COULD TELL BY HIS VOICE THAT HE WAS CONFUSED, SO I EXPLAINED WHICH RWY WAS WHICH (BY TELLING HIM THE RIGHT RWY WAS WHITE CONCRETE AND THE LEFT ONE WAS BLACK TOP) AND EXPLAINED THE PATTERN DIRECTION FOR BOTH RWYS. AT THE END OF THE XMISSION I RPTED TURNING A 3/4 MI FINAL. THE OTHER ACFT (AN SMA Y) RPTED DOWNWIND FOR 24R. MY STUDENT AND I LOOKED FOR THE OTHER ACFT IN THE PATTERN FOR 24R,BUT COULD NOT SEE HIM. WE ALSO RAISED BOTH WINGS AND LOOKED THROUGH THE SKYLIGHTS TO SEE IF HE WAS NEAR US. WE WERE LNDG USING A SHORT FIELD PROC, DID A GOOD T/D ON THE #'S, AND I APPLIED THE PWR SLOWLY TO START A TKOF. AS THE ENG STARTED TO ACCELERATE, SMA Y FLASHED IN FRONT OF US. WE LOCKED UP THE BRAKES AND AVOIDED THE CONTACT. AFTER LNDG I TALKED TO THE STUDENT IN THE OTHER ACFT AND DREW THE PATTERNS FOR THE RWYS ON HIS CLIPBOARD. HE WAS ONLY IN THE PATTERN ONCE BEFORE AND DIDN'T HAVE PERMISSION FROM HIS INSTR TO LAND AT OUR ARPT. I TALKED TO THE INSTR LATER ON THE PHONE, AND THE STUDENT WAS INFORMED OF THE RULES. HE JUST FORGOT. THE STUDENT HAD BEEN IN A LEFT DOWNWIND FOR 24R, WHEN A RIGHT PATTERN IS REQUIRED.

Data retrieved from NASA's ASRS site as of August 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.