Narrative:

We were beginning a training flight from manassas, and we were cleared by the tower to 'taxi into position and hold' on runway 16R, since traffic (a mooney) had just landed. My student took 15-30 seconds to taxi into position on the runway. I was prompting him about checking the windsock, and turning the transponder to altitude, and I didn't stop him when he advanced the throttle for takeoff. The runway was clear, however, we had not been given our takeoff clearance yet. When we were about 100-200 ft AGL in the climb out, the tower said 'cessna (call sign), in the future, please listen more carefully to your clearance, you were cleared to taxi into position and hold.' that was when I realized my error. I immediately apologized to the tower controller and said that I would be much more careful in the future. One contributing factor was that I was running behind for the flight lesson, and I may have been subconsciously rushing the student. When the student started to advance the throttle, I should have stopped him, and reminded him that we were only cleared into position and hold. I feel I got momentarily fixated on teaching the student about what to do when lining up on the runway, and I mistakenly thought we had been cleared for takeoff already, when in fact, we had not. Usually, I feel pretty good about my ability to multi-task, to teach, to listen, and respond to ATC, to be aware of airspace considerations, etc. However, I had a momentary lapse and allowed the student to begin the takeoff role prematurely. After we landed, the student and I discussed what happened, what should have been done, and ways to prevent that situation from happening again.

Google
 

Original NASA ASRS Text

Title: C172 FLT CREW TKOF WITHOUT CLRNC AT HEF.

Narrative: WE WERE BEGINNING A TRAINING FLT FROM MANASSAS, AND WE WERE CLRED BY THE TWR TO 'TAXI INTO POS AND HOLD' ON RWY 16R, SINCE TFC (A MOONEY) HAD JUST LANDED. MY STUDENT TOOK 15-30 SECONDS TO TAXI INTO POS ON THE RWY. I WAS PROMPTING HIM ABOUT CHKING THE WINDSOCK, AND TURNING THE XPONDER TO ALT, AND I DIDN'T STOP HIM WHEN HE ADVANCED THE THROTTLE FOR TKOF. THE RWY WAS CLR, HOWEVER, WE HAD NOT BEEN GIVEN OUR TKOF CLRNC YET. WHEN WE WERE ABOUT 100-200 FT AGL IN THE CLBOUT, THE TWR SAID 'CESSNA (CALL SIGN), IN THE FUTURE, PLEASE LISTEN MORE CAREFULLY TO YOUR CLRNC, YOU WERE CLRED TO TAXI INTO POS AND HOLD.' THAT WAS WHEN I REALIZED MY ERROR. I IMMEDIATELY APOLOGIZED TO THE TWR CTLR AND SAID THAT I WOULD BE MUCH MORE CAREFUL IN THE FUTURE. ONE CONTRIBUTING FACTOR WAS THAT I WAS RUNNING BEHIND FOR THE FLT LESSON, AND I MAY HAVE BEEN SUBCONSCIOUSLY RUSHING THE STUDENT. WHEN THE STUDENT STARTED TO ADVANCE THE THROTTLE, I SHOULD HAVE STOPPED HIM, AND REMINDED HIM THAT WE WERE ONLY CLRED INTO POS AND HOLD. I FEEL I GOT MOMENTARILY FIXATED ON TEACHING THE STUDENT ABOUT WHAT TO DO WHEN LINING UP ON THE RWY, AND I MISTAKENLY THOUGHT WE HAD BEEN CLRED FOR TKOF ALREADY, WHEN IN FACT, WE HAD NOT. USUALLY, I FEEL PRETTY GOOD ABOUT MY ABILITY TO MULTI-TASK, TO TEACH, TO LISTEN, AND RESPOND TO ATC, TO BE AWARE OF AIRSPACE CONSIDERATIONS, ETC. HOWEVER, I HAD A MOMENTARY LAPSE AND ALLOWED THE STUDENT TO BEGIN THE TKOF ROLE PREMATURELY. AFTER WE LANDED, THE STUDENT AND I DISCUSSED WHAT HAPPENED, WHAT SHOULD HAVE BEEN DONE, AND WAYS TO PREVENT THAT SIT FROM HAPPENING AGAIN.

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.