Narrative:

On the morning of jul/fri/99, I departed burbank with my 2 students on a tower en route clearance to john wayne/santa ana airport. The WX was VMC with unlimited ceiling, and good visibility. Approximately 15 mi out, socal approach began vectoring us for the ILS runway 19 approach. The student was flying the approach as I monitored the progress. The last ATC command was to fly present heading, vectors to localizer. At this point I turned my attention to my approach plates for the next departure route we would be requesting when on the ground. I estimate I had my head down for 15 seconds. During this time my student initiated a left turn of approximately 30 degrees. When I looked back up the airplane was level. I did not detect the heading change. Several moments later socal approach issued a command to turn immediately right, 260 degree heading. The left turn that my student initiated put us on an intercept heading for the localizer in direct conflict with other traffic. There were, in my opinion, several factors leading up to this incident. Allowing myself to be distracted, if only for a short period of time. The assumption on my part, that the student understood 'fly present heading' and that he would comply. Since the student had performed many approachs in the past and had no trouble previously dealing with ATC, I did not feel hesitant to prepare approach plates while he simply held a present heading.

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Original NASA ASRS Text

Title: A PA32 INSTRUCTOR PLT ALLOWS HIS STUDENT TO STRAY OFF AN ASSIGNED HEADING, CREATING A TFC CONFLICT DURING A VECTORED APCH TO SNA, CA

Narrative: ON THE MORNING OF JUL/FRI/99, I DEPARTED BURBANK WITH MY 2 STUDENTS ON A TWR ENRTE CLRNC TO JOHN WAYNE/SANTA ANA ARPT. THE WX WAS VMC WITH UNLIMITED CEILING, AND GOOD VISIBILITY. APPROX 15 MI OUT, SOCAL APCH BEGAN VECTORING US FOR THE ILS RWY 19 APCH. THE STUDENT WAS FLYING THE APCH AS I MONITORED THE PROGRESS. THE LAST ATC COMMAND WAS TO FLY PRESENT HEADING, VECTORS TO LOC. AT THIS POINT I TURNED MY ATTN TO MY APCH PLATES FOR THE NEXT DEP RTE WE WOULD BE REQUESTING WHEN ON THE GND. I ESTIMATE I HAD MY HEAD DOWN FOR 15 SECONDS. DURING THIS TIME MY STUDENT INITIATED A L TURN OF APPROX 30 DEGS. WHEN I LOOKED BACK UP THE AIRPLANE WAS LEVEL. I DID NOT DETECT THE HEADING CHANGE. SEVERAL MOMENTS LATER SOCAL APCH ISSUED A COMMAND TO TURN IMMEDIATELY R, 260 DEG HDG. THE L TURN THAT MY STUDENT INITIATED PUT US ON AN INTERCEPT HEADING FOR THE LOC IN DIRECT CONFLICT WITH OTHER TFC. THERE WERE, IN MY OPINION, SEVERAL FACTORS LEADING UP TO THIS INCIDENT. ALLOWING MYSELF TO BE DISTRACTED, IF ONLY FOR A SHORT PERIOD OF TIME. THE ASSUMPTION ON MY PART, THAT THE STUDENT UNDERSTOOD 'FLY PRESENT HEADING' AND THAT HE WOULD COMPLY. SINCE THE STUDENT HAD PERFORMED MANY APCHS IN THE PAST AND HAD NO TROUBLE PREVIOUSLY DEALING WITH ATC, I DID NOT FEEL HESITANT TO PREPARE APCH PLATES WHILE HE SIMPLY HELD A PRESENT HEADING.

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.