Narrative:

Flight was delayed 3 hours, with passenger loading called for clearance, flight plan had dropped out of system. There was a company flight plan that was to be ours later but because of the delay it was available. So we picked it up. However company had dispatched another aircraft inbound with the same flight number. We taxied out for departure when tower realized there would be 2 aircraft with the same call sign in the same airspace. In the future I will never use a flight number without getting an okay from flight following first. It would certainly have been easy enough to refile the original flight plan, delaying only a few mins a flight already over 2 hours late.

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Original NASA ASRS Text

Title: COMMUTER DEPARTS WITH CLRNC NOT YET IN EFFECT AFTER A 3 HR DELAY.

Narrative: FLT WAS DELAYED 3 HRS, WITH PAX LOADING CALLED FOR CLRNC, FLT PLAN HAD DROPPED OUT OF SYS. THERE WAS A COMPANY FLT PLAN THAT WAS TO BE OURS LATER BUT BECAUSE OF THE DELAY IT WAS AVAILABLE. SO WE PICKED IT UP. HOWEVER COMPANY HAD DISPATCHED ANOTHER ACFT INBOUND WITH THE SAME FLT NUMBER. WE TAXIED OUT FOR DEP WHEN TWR REALIZED THERE WOULD BE 2 ACFT WITH THE SAME CALL SIGN IN THE SAME AIRSPACE. IN THE FUTURE I WILL NEVER USE A FLT NUMBER WITHOUT GETTING AN OKAY FROM FLT FOLLOWING FIRST. IT WOULD CERTAINLY HAVE BEEN EASY ENOUGH TO REFILE THE ORIGINAL FLT PLAN, DELAYING ONLY A FEW MINS A FLT ALREADY OVER 2 HRS LATE.

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.