Narrative:

While taxiing out for departure the first officer called the tower for takeoff clearance. During the time the clearance was received the company radio which we were monitoring was busy with chatter. Upon receiving the clearance the first officer began his pre-departure announcement to the passenger. Upon reaching the end of the taxiway we taxied into position, completed our checklist, then began our takeoff roll. Once airborne tower came back over the radio and cleared us for takeoff. We called the tower back and told them that we understood that we had already been cleared for takeoff, to which the tower replied roger. After discussing the situation with the first officer we came to the conclusion that tower had used the phraseology, 'cleared into position and hold,' which according to the aim pilot/controller glossary should have been, 'taxi into position and hold.' combine the improper phraseology, background radio chatter and the first officer being out of the loop while making his pre-departure briefing, I misunderstood tower, thinking that they were clearing us for takeoff. Upon realizing our mistake I called tower back and apologized for the confusion on departure. Tower replied, 'no problem.' no hazard existed from this situation, fortunately.

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Original NASA ASRS Text

Title: DUE TO DISTRS IN THE COCKPIT CONFUSION AROSE CONCERNING THE TKOF AND AS A RESULT IT APPEARS THE REPORTER FLT DEPARTED WITHOUT TKOF CLRNC. CTLR PHRASEOLOGY MAY HAVE BEEN CONTRIBUTORY.

Narrative: WHILE TAXIING OUT FOR DEP THE F/O CALLED THE TWR FOR TKOF CLRNC. DURING THE TIME THE CLRNC WAS RECEIVED THE COMPANY RADIO WHICH WE WERE MONITORING WAS BUSY WITH CHATTER. UPON RECEIVING THE CLRNC THE F/O BEGAN HIS PRE-DEP ANNOUNCEMENT TO THE PAX. UPON REACHING THE END OF THE TXWY WE TAXIED INTO POS, COMPLETED OUR CHKLIST, THEN BEGAN OUR TKOF ROLL. ONCE AIRBORNE TWR CAME BACK OVER THE RADIO AND CLRED US FOR TKOF. WE CALLED THE TWR BACK AND TOLD THEM THAT WE UNDERSTOOD THAT WE HAD ALREADY BEEN CLRED FOR TKOF, TO WHICH THE TWR REPLIED ROGER. AFTER DISCUSSING THE SITUATION WITH THE F/O WE CAME TO THE CONCLUSION THAT TWR HAD USED THE PHRASEOLOGY, 'CLRED INTO POS AND HOLD,' WHICH ACCORDING TO THE AIM PLT/CTLR GLOSSARY SHOULD HAVE BEEN, 'TAXI INTO POS AND HOLD.' COMBINE THE IMPROPER PHRASEOLOGY, BACKGROUND RADIO CHATTER AND THE F/O BEING OUT OF THE LOOP WHILE MAKING HIS PRE-DEP BRIEFING, I MISUNDERSTOOD TWR, THINKING THAT THEY WERE CLRING US FOR TKOF. UPON REALIZING OUR MISTAKE I CALLED TWR BACK AND APOLOGIZED FOR THE CONFUSION ON DEP. TWR REPLIED, 'NO PROB.' NO HAZARD EXISTED FROM THIS SITUATION, FORTUNATELY.

Data retrieved from NASA's ASRS site as of August 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.