Narrative:

Small aircraft X, a student pilot, called ready for departure at end of runway 35 for touch and go on the pattern. I told small aircraft X 'runway 35, make right closed traffic, maintain at or below 2000, cleared for takeoff, traffic is an small aircraft on 2 1/2 mi final runway 13.' small aircraft X acknowledged and departed. My attention was diverted to a ground situation involving a progressive taxi; I did not see small aircraft X make his crosswind turnout. Approximately 30 seconds later, small aircraft Y on the ILS runway 13 final approach course, advised he had a near miss with an small aircraft and requested its location. The pilot of small aircraft X replied he was on a left downwind for runway 35. Both aircraft landed without incident. A number of factors entered into this near miss situation. The pilot of small aircraft X did not follow ATC instructions to enter right traffic, even after pertinent traffic was issued. Pilot should have been aware that a left turnout off runway 35 would have put his aircraft in direct conflict with small aircraft Y. Controller should have ensured small aircraft X complied with ATC instructions, especially considering the proximity of aircraft involved and marginal WX conditions. Instead, controller's attention was drawn to a situation of lesser priority (ground control instructions). The university flight school the student is associated with constitutes a large number of operations at the airport; relations between the tower and school are close. Consequently, I feel some complacency on my part concerning the proficiency of the student pilot led me to divert my attention to a lesser priority. I assumed the pilot of small aircraft X was capable of understanding and following ATC instructions based upon past experience. I let my guard down at a most inopportune time. Present during this incident was a developmental who was watching the local controller. He watched small aircraft X make a left turnout, was at least cognizant of a developing conflict, yet was unsure whether he should 'challenge' the operations of an fpl. Instead, he asked me if small aircraft X was supposed to be in right traffic, and I replied affirmatively. It never struck me that something was wrong until after the fact. Had the developmental said something about left traffic, I may have responded much quicker to the developing situation.

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Original NASA ASRS Text

Title: SMA X NON ADHERENCE TO ATC CLRNC HAD NMAC WITH SMA Y. PLTDEV. SEE AND AVOID CONCEPT.

Narrative: SMA X, A STUDENT PLT, CALLED READY FOR DEP AT END OF RWY 35 FOR TOUCH AND GO ON THE PATTERN. I TOLD SMA X 'RWY 35, MAKE R CLOSED TFC, MAINTAIN AT OR BELOW 2000, CLRED FOR TKOF, TFC IS AN SMA ON 2 1/2 MI FINAL RWY 13.' SMA X ACKNOWLEDGED AND DEPARTED. MY ATTN WAS DIVERTED TO A GND SITUATION INVOLVING A PROGRESSIVE TAXI; I DID NOT SEE SMA X MAKE HIS XWIND TURNOUT. APPROX 30 SECONDS LATER, SMA Y ON THE ILS RWY 13 FINAL APCH COURSE, ADVISED HE HAD A NEAR MISS WITH AN SMA AND REQUESTED ITS LOCATION. THE PLT OF SMA X REPLIED HE WAS ON A L DOWNWIND FOR RWY 35. BOTH ACFT LANDED WITHOUT INCIDENT. A NUMBER OF FACTORS ENTERED INTO THIS NEAR MISS SITUATION. THE PLT OF SMA X DID NOT FOLLOW ATC INSTRUCTIONS TO ENTER R TFC, EVEN AFTER PERTINENT TFC WAS ISSUED. PLT SHOULD HAVE BEEN AWARE THAT A L TURNOUT OFF RWY 35 WOULD HAVE PUT HIS ACFT IN DIRECT CONFLICT WITH SMA Y. CTLR SHOULD HAVE ENSURED SMA X COMPLIED WITH ATC INSTRUCTIONS, ESPECIALLY CONSIDERING THE PROX OF ACFT INVOLVED AND MARGINAL WX CONDITIONS. INSTEAD, CTLR'S ATTN WAS DRAWN TO A SITUATION OF LESSER PRIORITY (GND CTL INSTRUCTIONS). THE UNIVERSITY FLT SCHOOL THE STUDENT IS ASSOCIATED WITH CONSTITUTES A LARGE NUMBER OF OPS AT THE ARPT; RELATIONS BTWN THE TWR AND SCHOOL ARE CLOSE. CONSEQUENTLY, I FEEL SOME COMPLACENCY ON MY PART CONCERNING THE PROFICIENCY OF THE STUDENT PLT LED ME TO DIVERT MY ATTN TO A LESSER PRIORITY. I ASSUMED THE PLT OF SMA X WAS CAPABLE OF UNDERSTANDING AND FOLLOWING ATC INSTRUCTIONS BASED UPON PAST EXPERIENCE. I LET MY GUARD DOWN AT A MOST INOPPORTUNE TIME. PRESENT DURING THIS INCIDENT WAS A DEVELOPMENTAL WHO WAS WATCHING THE LCL CTLR. HE WATCHED SMA X MAKE A L TURNOUT, WAS AT LEAST COGNIZANT OF A DEVELOPING CONFLICT, YET WAS UNSURE WHETHER HE SHOULD 'CHALLENGE' THE OPS OF AN FPL. INSTEAD, HE ASKED ME IF SMA X WAS SUPPOSED TO BE IN R TFC, AND I REPLIED AFFIRMATIVELY. IT NEVER STRUCK ME THAT SOMETHING WAS WRONG UNTIL AFTER THE FACT. HAD THE DEVELOPMENTAL SAID SOMETHING ABOUT L TFC, I MAY HAVE RESPONDED MUCH QUICKER TO THE DEVELOPING SITUATION.

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.