Narrative:

During an FAA observed check ride for a company initial check, we departed ZZZ on an IFR flight plan. After briefing the departure and completing our checklist, we were cleared for takeoff on runway 16L 'aircraft X cleared for takeoff runway 16L, citation traffic 5 mi final.' I acknowledged clear for takeoff on runway 16L. Then, the controller cleared us for takeoff runway 16L, no delay.' we had already begun the roll with power application and acknowledged. The takeoff commenced normally. Tower then called us after takeoff, and we were in the process of executing an after takeoff engine failure (at approximately 600 ft AGL). I heard the tower call our number, and I believed he (controller) told us to switch to departure. The check airman also thought tower told us to switch to departure, but it was during a critical phase of flight and was the only time communication was ever not 100% assured. We switched over to departure and didn't find out about the misunderstanding until later. Apparently, the tower controller claimed he canceled our takeoff clearance at some point after we were cleared for takeoff. My only thought is that tower may have given us the canceled takeoff clearance while I was on the radio replying to him and the transmission could have been blocked. The FAA inspector, check airman and myself all positively recall, with confidence, we did not fail to reply to a readable clearance on the ground.

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Original NASA ASRS Text

Title: PLTS TAKE OFF WITHOUT CLRNC.

Narrative: DURING AN FAA OBSERVED CHK RIDE FOR A COMPANY INITIAL CHK, WE DEPARTED ZZZ ON AN IFR FLT PLAN. AFTER BRIEFING THE DEP AND COMPLETING OUR CHKLIST, WE WERE CLRED FOR TKOF ON RWY 16L 'ACFT X CLRED FOR TKOF RWY 16L, CITATION TFC 5 MI FINAL.' I ACKNOWLEDGED CLR FOR TKOF ON RWY 16L. THEN, THE CTLR CLRED US FOR TKOF RWY 16L, NO DELAY.' WE HAD ALREADY BEGUN THE ROLL WITH PWR APPLICATION AND ACKNOWLEDGED. THE TKOF COMMENCED NORMALLY. TWR THEN CALLED US AFTER TKOF, AND WE WERE IN THE PROCESS OF EXECUTING AN AFTER TKOF ENG FAILURE (AT APPROX 600 FT AGL). I HEARD THE TWR CALL OUR NUMBER, AND I BELIEVED HE (CTLR) TOLD US TO SWITCH TO DEP. THE CHK AIRMAN ALSO THOUGHT TWR TOLD US TO SWITCH TO DEP, BUT IT WAS DURING A CRITICAL PHASE OF FLT AND WAS THE ONLY TIME COM WAS EVER NOT 100% ASSURED. WE SWITCHED OVER TO DEP AND DIDN'T FIND OUT ABOUT THE MISUNDERSTANDING UNTIL LATER. APPARENTLY, THE TWR CTLR CLAIMED HE CANCELED OUR TKOF CLRNC AT SOME POINT AFTER WE WERE CLRED FOR TKOF. MY ONLY THOUGHT IS THAT TWR MAY HAVE GIVEN US THE CANCELED TKOF CLRNC WHILE I WAS ON THE RADIO REPLYING TO HIM AND THE XMISSION COULD HAVE BEEN BLOCKED. THE FAA INSPECTOR, CHK AIRMAN AND MYSELF ALL POSITIVELY RECALL, WITH CONFIDENCE, WE DID NOT FAIL TO REPLY TO A READABLE CLRNC ON THE GND.

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.