Narrative:

I am a CFI and was flying with a student. We taxied from tiedown at hpn, did our runup, and we were #1 in sequence for departure on runway 16. The student was handling all communications with ATC. The student talked to the tower and we taxied onto the runway. After positioning the aircraft for takeoff, the student sat there without initiating the takeoff. I prompted the student to begin the takeoff. The student indicated that he didn't remember hearing that we were 'cleared for takeoff.' I indicated that we were in fact cleared and that he should initiate the takeoff, which he did. Just as the airplane lifted off of the runway, ATC called us with a 'cleared for takeoff.' I responded to ATC by repeating that we were 'cleared for takeoff.' approximately 30 seconds after this exchange with ATC, when we were approximately 200-300 ft above the runway, the controller called us and said that she didn't remember clearing us for takeoff prior to our initiating our takeoff roll. She further indicated that a king air had been cleared across the far end of the runway. I did see the king air as we lifted off from the runway but it was already off of runway 16 and onto a taxiway on the east side of the airport. I responded to her inquiry by indicating that I was probably at fault. She didn't say anything further.

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Original NASA ASRS Text

Title: A LOW TIME CFI BECAME CONFUSED WHEN HIS STUDENT LINED UP ON THE RWY BUT DID NOT TAKE OFF. THE LOW TIME CFI DIRECTED THE STUDENT TO TAKE OFF. THOUGH THE STUDENT SAID THEY HAD NOT BEEN CLRED, HE THEN COMPLIED WITH HIS CFI. AS THEY ROTATED, TWR CALLED AND SAID THEY HAD NOT BEEN CLRED FOR TKOF.

Narrative: I AM A CFI AND WAS FLYING WITH A STUDENT. WE TAXIED FROM TIEDOWN AT HPN, DID OUR RUNUP, AND WE WERE #1 IN SEQUENCE FOR DEP ON RWY 16. THE STUDENT WAS HANDLING ALL COMS WITH ATC. THE STUDENT TALKED TO THE TWR AND WE TAXIED ONTO THE RWY. AFTER POSITIONING THE ACFT FOR TKOF, THE STUDENT SAT THERE WITHOUT INITIATING THE TKOF. I PROMPTED THE STUDENT TO BEGIN THE TKOF. THE STUDENT INDICATED THAT HE DIDN'T REMEMBER HEARING THAT WE WERE 'CLRED FOR TKOF.' I INDICATED THAT WE WERE IN FACT CLRED AND THAT HE SHOULD INITIATE THE TKOF, WHICH HE DID. JUST AS THE AIRPLANE LIFTED OFF OF THE RWY, ATC CALLED US WITH A 'CLRED FOR TKOF.' I RESPONDED TO ATC BY REPEATING THAT WE WERE 'CLRED FOR TKOF.' APPROX 30 SECONDS AFTER THIS EXCHANGE WITH ATC, WHEN WE WERE APPROX 200-300 FT ABOVE THE RWY, THE CTLR CALLED US AND SAID THAT SHE DIDN'T REMEMBER CLRING US FOR TKOF PRIOR TO OUR INITIATING OUR TKOF ROLL. SHE FURTHER INDICATED THAT A KING AIR HAD BEEN CLRED ACROSS THE FAR END OF THE RWY. I DID SEE THE KING AIR AS WE LIFTED OFF FROM THE RWY BUT IT WAS ALREADY OFF OF RWY 16 AND ONTO A TXWY ON THE E SIDE OF THE ARPT. I RESPONDED TO HER INQUIRY BY INDICATING THAT I WAS PROBABLY AT FAULT. SHE DIDN'T SAY ANYTHING FURTHER.

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.