Narrative:

During a busy moment at vrb, several aircraft on approach and holding in sequence to depart runway 4. I had the controls about to demonstrate soft field takeoff procedures to a student pilot. When we got to the #1 position, and before I reported in, clearance was given for immediate takeoff. I had not reported position yet due to heavy radio sequencing by ATC and I assumed clearance was given in this manner for prompt traffic flow. Aircraft on final was visually verified for enough separation clearance, so as I accepted the clearance and rolled for the runway, at the same time, I noticed a cessna rolling for an intersection takeoff 1/2 way down the runway. ATC announced the intersection takeoff clearance was given to a cessna. I announced my confusion as I promptly continued to a taxiway directly opposite on the other side of the departure end. No action was needed by the approach traffic nor instruction given by ATC to disrupt the original ongoing flow. Eventually we were cleared third for takeoff after the traffic that had been in sequence behind me, and nothing was said by ATC. I cannot say whether the cessna had a similar tail number or the controller used mine to clear it. My student also believed it was us who had been cleared, until corrective action was taken. The cessna was the only other traffic for an intersection departure and I was not aware of its presence. Factors were: the heavy traffic at the time, rush to accept a clearance before verifying and lack of awareness of other traffic holding for intersection departure on the same runway, visually because I was preoccupied with the approaching traffic and aurally because I had switched to tower frequency but only a few moments before.

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Original NASA ASRS Text

Title: A RWY INCURSION OCCURS WHEN A PA28 CFI MOVES ONTO RWY FOR TKOF USING A CLRNC ISSUED TO A CESSNA FOR AN INTXN TKOF AT VRB, FL.

Narrative: DURING A BUSY MOMENT AT VRB, SEVERAL ACFT ON APCH AND HOLDING IN SEQUENCE TO DEPART RWY 4. I HAD THE CTLS ABOUT TO DEMONSTRATE SOFT FIELD TKOF PROCS TO A STUDENT PLT. WHEN WE GOT TO THE #1 POS, AND BEFORE I RPTED IN, CLRNC WAS GIVEN FOR IMMEDIATE TKOF. I HAD NOT RPTED POS YET DUE TO HVY RADIO SEQUENCING BY ATC AND I ASSUMED CLRNC WAS GIVEN IN THIS MANNER FOR PROMPT TFC FLOW. ACFT ON FINAL WAS VISUALLY VERIFIED FOR ENOUGH SEPARATION CLRNC, SO AS I ACCEPTED THE CLRNC AND ROLLED FOR THE RWY, AT THE SAME TIME, I NOTICED A CESSNA ROLLING FOR AN INTXN TKOF 1/2 WAY DOWN THE RWY. ATC ANNOUNCED THE INTXN TKOF CLRNC WAS GIVEN TO A CESSNA. I ANNOUNCED MY CONFUSION AS I PROMPTLY CONTINUED TO A TXWY DIRECTLY OPPOSITE ON THE OTHER SIDE OF THE DEP END. NO ACTION WAS NEEDED BY THE APCH TFC NOR INSTRUCTION GIVEN BY ATC TO DISRUPT THE ORIGINAL ONGOING FLOW. EVENTUALLY WE WERE CLRED THIRD FOR TKOF AFTER THE TFC THAT HAD BEEN IN SEQUENCE BEHIND ME, AND NOTHING WAS SAID BY ATC. I CANNOT SAY WHETHER THE CESSNA HAD A SIMILAR TAIL NUMBER OR THE CTLR USED MINE TO CLR IT. MY STUDENT ALSO BELIEVED IT WAS US WHO HAD BEEN CLRED, UNTIL CORRECTIVE ACTION WAS TAKEN. THE CESSNA WAS THE ONLY OTHER TFC FOR AN INTXN DEP AND I WAS NOT AWARE OF ITS PRESENCE. FACTORS WERE: THE HVY TFC AT THE TIME, RUSH TO ACCEPT A CLRNC BEFORE VERIFYING AND LACK OF AWARENESS OF OTHER TFC HOLDING FOR INTXN DEP ON THE SAME RWY, VISUALLY BECAUSE I WAS PREOCCUPIED WITH THE APCHING TFC AND AURALLY BECAUSE I HAD SWITCHED TO TWR FREQ BUT ONLY A FEW MOMENTS BEFORE.

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.