Narrative:

At farmingdale's republic airport, I inadvertently taxied to the wrong runway and in so doing, I crossed over the active runway by mistake. I did not immediately realize my mistake because I was adjusting my passenger's (student) shoulder harness while I allowed him to taxi the aircraft. Once I crossed over the runway, we continued to the run-up area when I finally realized that I was not positioned correctly and that I crossed over the active runway. I advised the tower that I was holding short of the wrong runway for takeoff, and they questioned my actions. After a few mins, I was allowed to depart on the inactive runway without incident. I realize the gravity of my mistake and take full responsibility for becoming distraction while taxiing and not supervising my student fully. Despite having the current ATIS information, a taxi clearance, and being thoroughly familiar with republic airport, my lack of attention created a potentially dangerous situation. I am grateful that my error did not cause an accident, and to my knowledge, no other pilots were affected by my mistake (aborted takeoff, go around, etc). I greatly appreciate the professional manner with which the republic air traffic controllers handled this matter at the time of its occurrence. I reported this incident to my employer who admonished me for my lack of student supervision and attention while taxiing.

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Original NASA ASRS Text

Title: RWY INCURSION OCCURS WHEN A PA28 INSTRUCTOR PLT ALLOWS HIS STUDENT PLT TO TAXI ACROSS AN ACTIVE RWY AT FRG, NY.

Narrative: AT FARMINGDALE'S REPUBLIC ARPT, I INADVERTENTLY TAXIED TO THE WRONG RWY AND IN SO DOING, I CROSSED OVER THE ACTIVE RWY BY MISTAKE. I DID NOT IMMEDIATELY REALIZE MY MISTAKE BECAUSE I WAS ADJUSTING MY PAX'S (STUDENT) SHOULDER HARNESS WHILE I ALLOWED HIM TO TAXI THE ACFT. ONCE I CROSSED OVER THE RWY, WE CONTINUED TO THE RUN-UP AREA WHEN I FINALLY REALIZED THAT I WAS NOT POSITIONED CORRECTLY AND THAT I CROSSED OVER THE ACTIVE RWY. I ADVISED THE TWR THAT I WAS HOLDING SHORT OF THE WRONG RWY FOR TKOF, AND THEY QUESTIONED MY ACTIONS. AFTER A FEW MINS, I WAS ALLOWED TO DEPART ON THE INACTIVE RWY WITHOUT INCIDENT. I REALIZE THE GRAVITY OF MY MISTAKE AND TAKE FULL RESPONSIBILITY FOR BECOMING DISTR WHILE TAXIING AND NOT SUPERVISING MY STUDENT FULLY. DESPITE HAVING THE CURRENT ATIS INFO, A TAXI CLRNC, AND BEING THOROUGHLY FAMILIAR WITH REPUBLIC ARPT, MY LACK OF ATTN CREATED A POTENTIALLY DANGEROUS SIT. I AM GRATEFUL THAT MY ERROR DID NOT CAUSE AN ACCIDENT, AND TO MY KNOWLEDGE, NO OTHER PLTS WERE AFFECTED BY MY MISTAKE (ABORTED TKOF, GAR, ETC). I GREATLY APPRECIATE THE PROFESSIONAL MANNER WITH WHICH THE REPUBLIC AIR TFC CTLRS HANDLED THIS MATTER AT THE TIME OF ITS OCCURRENCE. I RPTED THIS INCIDENT TO MY EMPLOYER WHO ADMONISHED ME FOR MY LACK OF STUDENT SUPERVISION AND ATTN WHILE TAXIING.

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.