Narrative:

On jan/wed/02, I went to louisville FSS at louisville bowman and obtained a WX briefing. The conditions on my route required an IFR flight plan. After leaving FSS, I returned to my hangar to preflight. Because the tower was not open, I contacted louisville radio for a TA. The operator offered to activate my flight plan, to which I accepted. While taxiing to runway 6, he called back with my clearance information. I documented my information, and he verified my readback. While holding for clearance, traffic chopper (the XA40 traffic helicopter) called louisville radio for a TA. The operator told the helicopter that the only known traffic was a lance that would be departing within 2 mins. Based on that transmission, I quickly finished my run-up so I could be in the air within the 2 mins. I knew the helicopter was approaching and I wanted to be gone before he arrived. Once airborne, while still in VMC and outside class C airspace, I contacted louisville departure on the frequency I was given, and reported off bowman. The controller acknowledged my presence and I began my flight. Several mins into the flight I was advised that I departed bowman without clearance, however, it wasn't a big deal because there were no other aircraft involved. Shortly before I left their airspace, I was asked to contact louisville approach control after landing. This was purely a case of misunderstanding between the pilot (myself) and louisville radio. I misunderstood a communication between radio and a helicopter to infer that I was about to depart. If radio would have informed the helicopter that I was still holding for a clearance, I would not have departed. I am used to either departing with a tower, or in uncontrolled airspace.

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Original NASA ASRS Text

Title: PA32 PLT DEPARTED ON AN IFR FLT PLAN WITHOUT WAITING FOR A DEP RELEASE.

Narrative: ON JAN/WED/02, I WENT TO LOUISVILLE FSS AT LOUISVILLE BOWMAN AND OBTAINED A WX BRIEFING. THE CONDITIONS ON MY RTE REQUIRED AN IFR FLT PLAN. AFTER LEAVING FSS, I RETURNED TO MY HANGAR TO PREFLT. BECAUSE THE TWR WAS NOT OPEN, I CONTACTED LOUISVILLE RADIO FOR A TA. THE OPERATOR OFFERED TO ACTIVATE MY FLT PLAN, TO WHICH I ACCEPTED. WHILE TAXIING TO RWY 6, HE CALLED BACK WITH MY CLRNC INFO. I DOCUMENTED MY INFO, AND HE VERIFIED MY READBACK. WHILE HOLDING FOR CLRNC, TFC CHOPPER (THE XA40 TFC HELI) CALLED LOUISVILLE RADIO FOR A TA. THE OPERATOR TOLD THE HELI THAT THE ONLY KNOWN TFC WAS A LANCE THAT WOULD BE DEPARTING WITHIN 2 MINS. BASED ON THAT XMISSION, I QUICKLY FINISHED MY RUN-UP SO I COULD BE IN THE AIR WITHIN THE 2 MINS. I KNEW THE HELI WAS APCHING AND I WANTED TO BE GONE BEFORE HE ARRIVED. ONCE AIRBORNE, WHILE STILL IN VMC AND OUTSIDE CLASS C AIRSPACE, I CONTACTED LOUISVILLE DEP ON THE FREQ I WAS GIVEN, AND RPTED OFF BOWMAN. THE CTLR ACKNOWLEDGED MY PRESENCE AND I BEGAN MY FLT. SEVERAL MINS INTO THE FLT I WAS ADVISED THAT I DEPARTED BOWMAN WITHOUT CLRNC, HOWEVER, IT WASN'T A BIG DEAL BECAUSE THERE WERE NO OTHER ACFT INVOLVED. SHORTLY BEFORE I LEFT THEIR AIRSPACE, I WAS ASKED TO CONTACT LOUISVILLE APCH CTL AFTER LNDG. THIS WAS PURELY A CASE OF MISUNDERSTANDING BTWN THE PLT (MYSELF) AND LOUISVILLE RADIO. I MISUNDERSTOOD A COM BTWN RADIO AND A HELI TO INFER THAT I WAS ABOUT TO DEPART. IF RADIO WOULD HAVE INFORMED THE HELI THAT I WAS STILL HOLDING FOR A CLRNC, I WOULD NOT HAVE DEPARTED. I AM USED TO EITHER DEPARTING WITH A TWR, OR IN UNCTLED AIRSPACE.

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.