Narrative:

On the landing rollout; ATC (tower) gave me a clearance to exit at a specific intersection; hold short of the parallel runway; and stay on that frequency. My student was asking a question during the busy radio exchanges. I acknowledged the instruction but thought I had heard the instruction to taxi across the parallel runway. So I went ahead and taxied across. However the tower had cleared an aircraft (a commercial airliner) to takeoff on that runway (on another frequency- that airport uses different frequencies for different runways). I saw the airplane holding and taxied across. However; he had been cleared and was beginning his takeoff roll. I was across the runway before the aircraft taking off reached my position but it was too close. The lesson here is not to let a student distract you with a question during high work-load phases of a training flight. He was a new student and did not know to not ask questions then.

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Original NASA ASRS Text

Title: A flight instructor reported that he became distracted by his student's question during taxi and crossed onto an active runway as an air carrier began a takeoff roll.

Narrative: On the landing rollout; ATC (tower) gave me a clearance to Exit at a specific intersection; hold short of the parallel runway; and stay on that frequency. My student was asking a question during the busy radio exchanges. I acknowledged the instruction but thought I had heard the instruction to taxi across the parallel runway. So I went ahead and taxied across. However the tower had cleared an aircraft (a commercial airliner) to takeoff on that runway (on another frequency- that airport uses different frequencies for different runways). I saw the airplane holding and taxied across. However; he had been cleared and was beginning his takeoff roll. I was across the runway before the aircraft taking off reached my position but it was too close. The lesson here is not to let a student distract you with a question during high work-load phases of a training flight. He was a new student and did not know to not ask questions then.

Data retrieved from NASA's ASRS site 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.