Narrative:

Received an IFR flight plan on the ground at fmy. The clearance was understood by the pilot 'as filed,' and that was confirmed on the readback. On departure, page tower advised me to contact departure. Upon switching over to departure, I proceeded on course as filed. Shortly thereafter, departure requested me to do an immediate left turn to 090 degrees. Departure indicated a traffic conflict with a commercial jet landing rsw. Departure was surprised I had proceeded on course because he thought I was instructed to maintain runway heading out of fmy. That direction was obviously not part of my clearance. I don't know if there was any traffic interruption at all at rsw.

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Original NASA ASRS Text

Title: A PA28-180 PVT PLT DEPARTED FMY, FL, TURNED OFF HIS DESIGNATED RWY HDG TO 'ON COURSE' AND ALMOST CONFLICTED WITH INBOUND TFC AT RSW.

Narrative: RECEIVED AN IFR FLT PLAN ON THE GND AT FMY. THE CLRNC WAS UNDERSTOOD BY THE PLT 'AS FILED,' AND THAT WAS CONFIRMED ON THE READBACK. ON DEP, PAGE TWR ADVISED ME TO CONTACT DEP. UPON SWITCHING OVER TO DEP, I PROCEEDED ON COURSE AS FILED. SHORTLY THEREAFTER, DEP REQUESTED ME TO DO AN IMMEDIATE L TURN TO 090 DEGS. DEP INDICATED A TFC CONFLICT WITH A COMMERCIAL JET LNDG RSW. DEP WAS SURPRISED I HAD PROCEEDED ON COURSE BECAUSE HE THOUGHT I WAS INSTRUCTED TO MAINTAIN RWY HDG OUT OF FMY. THAT DIRECTION WAS OBVIOUSLY NOT PART OF MY CLRNC. I DON'T KNOW IF THERE WAS ANY TFC INTERRUPTION AT ALL AT RSW.

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.