Narrative:

I was the PIC serving as a line check airman; and my first officer was a new hire on his second day of IOE. We departed the terminal gate and taxied to runway 27 where we were instructed to hold short. After holding short for about 10-15 mins; another aircraft landed and exited the runway at which point I queried the tower that we were still holding short of runway 27. The tower cleared us to taxi into position and hold runway 27 at which time the first officer claims he read back the clearance. I thought the tower cleared us for takeoff. While taxiing out; the first officer and I were discussing takeoff techniques since the first officer had previously been rotating with excessively high pitch attitudes; coming close to striking the tail. Once lined up with the runway; I relinquished controls to the first officer whose leg it was to fly. He brought up the power levers and we proceeded to take off. Once airborne; cys tower advised us that we were not cleared for takeoff and asked if we could remain VFR. I apologized and stated that I thought we were cleared for takeoff; however; we could remain VFR and provide our own terrain separation throughout the climb since the WX was 10+ mi visibility and clear skies. Cys tower advised us to maintain VFR and switch to ZDV where we could pick up our clearance. I apologized for the miscom and contacted ZDV where we received our IFR clearance to den and the rest of the trip was uneventful.

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Original NASA ASRS Text

Title: BE1900 FLT CREW DEPARTS CYS WITHOUT A TKOF CLRNC.

Narrative: I WAS THE PIC SERVING AS A LINE CHK AIRMAN; AND MY FO WAS A NEW HIRE ON HIS SECOND DAY OF IOE. WE DEPARTED THE TERMINAL GATE AND TAXIED TO RWY 27 WHERE WE WERE INSTRUCTED TO HOLD SHORT. AFTER HOLDING SHORT FOR ABOUT 10-15 MINS; ANOTHER ACFT LANDED AND EXITED THE RWY AT WHICH POINT I QUERIED THE TWR THAT WE WERE STILL HOLDING SHORT OF RWY 27. THE TWR CLRED US TO TAXI INTO POS AND HOLD RWY 27 AT WHICH TIME THE FO CLAIMS HE READ BACK THE CLRNC. I THOUGHT THE TWR CLRED US FOR TKOF. WHILE TAXIING OUT; THE FO AND I WERE DISCUSSING TKOF TECHNIQUES SINCE THE FO HAD PREVIOUSLY BEEN ROTATING WITH EXCESSIVELY HIGH PITCH ATTITUDES; COMING CLOSE TO STRIKING THE TAIL. ONCE LINED UP WITH THE RWY; I RELINQUISHED CTLS TO THE FO WHOSE LEG IT WAS TO FLY. HE BROUGHT UP THE PWR LEVERS AND WE PROCEEDED TO TAKE OFF. ONCE AIRBORNE; CYS TWR ADVISED US THAT WE WERE NOT CLRED FOR TKOF AND ASKED IF WE COULD REMAIN VFR. I APOLOGIZED AND STATED THAT I THOUGHT WE WERE CLRED FOR TKOF; HOWEVER; WE COULD REMAIN VFR AND PROVIDE OUR OWN TERRAIN SEPARATION THROUGHOUT THE CLB SINCE THE WX WAS 10+ MI VISIBILITY AND CLR SKIES. CYS TWR ADVISED US TO MAINTAIN VFR AND SWITCH TO ZDV WHERE WE COULD PICK UP OUR CLRNC. I APOLOGIZED FOR THE MISCOM AND CONTACTED ZDV WHERE WE RECEIVED OUR IFR CLRNC TO DEN AND THE REST OF THE TRIP WAS UNEVENTFUL.

Data retrieved from NASA's ASRS site as of January 2009 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.