Narrative:

I received the clearance for our flight at approximately XA52. We were cleared as filed and I called ground for a taxi clearance because there was a current ATIS broadcasting and I thought the tower was open. The tower responded on the CTAF and stated that he was not yet open, but he told us which runway was active. We began taxiing to the runway assuming that the tower would be open by the time we reached the end of the runway. As we began our taxi, the tower came on the frequency again and stated that the other runway would be available. Since it was a quicker taxi, we told him that we would accept the other runway. As we approached the end of the runway, our clock showed XB00, so we called the tower and asked him if he was open yet. He said it would still be another min. Then as we came to a stop at the hold short line, the tower called us one more time and advised that he wouldn't be open for a few more seconds, but that we either wait or else go ahead and take off. We departed the airport and then called departure and had an uneventful flight. Looking back, I am not sure if the tower was allowed to release us before the official opening. The several communications back and forth particularly the final one at XB00 telling us that we could go ahead and depart led us to believe that he was coordinating the local traffic. We assumed he had provided our release when he told us we could take off. He told us this at XB00 and then as we were taking off he officially announced the airport was open. Since it was just a matter of seconds, we thought everything was handled legally. I think it would be less confusing, particularly at XB00, if the tower did not broadcast on the frequency until if was officially opened.

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Original NASA ASRS Text

Title: A DHC8 CREW DEPART CHO A FEW SECONDS BEFORE THE TWR WAS OFFICIALLY OPEN. CREW WAS CONCERNED WITH THE CTLR'S COMMENT THAT THE TWR WAS NOT OPEN YET, BUT THAT THEY EITHER WAIT OR ELSE GO AHEAD AND TAKE OFF.

Narrative: I RECEIVED THE CLRNC FOR OUR FLT AT APPROX XA52. WE WERE CLRED AS FILED AND I CALLED GND FOR A TAXI CLRNC BECAUSE THERE WAS A CURRENT ATIS BROADCASTING AND I THOUGHT THE TWR WAS OPEN. THE TWR RESPONDED ON THE CTAF AND STATED THAT HE WAS NOT YET OPEN, BUT HE TOLD US WHICH RWY WAS ACTIVE. WE BEGAN TAXIING TO THE RWY ASSUMING THAT THE TWR WOULD BE OPEN BY THE TIME WE REACHED THE END OF THE RWY. AS WE BEGAN OUR TAXI, THE TWR CAME ON THE FREQ AGAIN AND STATED THAT THE OTHER RWY WOULD BE AVAILABLE. SINCE IT WAS A QUICKER TAXI, WE TOLD HIM THAT WE WOULD ACCEPT THE OTHER RWY. AS WE APCHED THE END OF THE RWY, OUR CLOCK SHOWED XB00, SO WE CALLED THE TWR AND ASKED HIM IF HE WAS OPEN YET. HE SAID IT WOULD STILL BE ANOTHER MIN. THEN AS WE CAME TO A STOP AT THE HOLD SHORT LINE, THE TWR CALLED US ONE MORE TIME AND ADVISED THAT HE WOULDN'T BE OPEN FOR A FEW MORE SECONDS, BUT THAT WE EITHER WAIT OR ELSE GO AHEAD AND TAKE OFF. WE DEPARTED THE ARPT AND THEN CALLED DEP AND HAD AN UNEVENTFUL FLT. LOOKING BACK, I AM NOT SURE IF THE TWR WAS ALLOWED TO RELEASE US BEFORE THE OFFICIAL OPENING. THE SEVERAL COMS BACK AND FORTH PARTICULARLY THE FINAL ONE AT XB00 TELLING US THAT WE COULD GO AHEAD AND DEPART LED US TO BELIEVE THAT HE WAS COORDINATING THE LCL TFC. WE ASSUMED HE HAD PROVIDED OUR RELEASE WHEN HE TOLD US WE COULD TAKE OFF. HE TOLD US THIS AT XB00 AND THEN AS WE WERE TAKING OFF HE OFFICIALLY ANNOUNCED THE ARPT WAS OPEN. SINCE IT WAS JUST A MATTER OF SECONDS, WE THOUGHT EVERYTHING WAS HANDLED LEGALLY. I THINK IT WOULD BE LESS CONFUSING, PARTICULARLY AT XB00, IF THE TWR DID NOT BROADCAST ON THE FREQ UNTIL IF WAS OFFICIALLY OPENED.

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.