GA SMA DEVIATED FROM CLRNC. HEADING DEVIATION.

Narrative

THE INCIDENT; A DEVIATION FROM ASSIGNED HDG; OCCURRED 11/88 IMMEDIATELY AFTER TKOF FROM TYS. I HAD RECEIVED CLRNC TO CHA AS FILED; DEP 123.9; AND FLY HDG 020 DEGS. WHEN CLRED FOR TKOF ON RWY 5R I WAS GIVEN A WAKE TURB CAUTION RE: A TRANSPORT SIZE ACFT WHICH HAD JUST TAKEN OFF FROM RWY 5L. I COULD SEE THE ACFT IN THE DISTANCE. ON THE TKOF ROLL I BECAME VERY CONCERNED THAT A HDG OF 020 DEGS WOULD PUT ME IN TRAIL BEHIND THE LARGER ACFT. I TRIED TO CLB SO AS TO BE ABOVE THE LARGER PLANE'S FLT PATH AND BEGAN A TURN TO THE LEFT TO CROSS ITS FLT PATH. UNFORTUNATELY; I DID NOT COM MY CONCERN TO ATC. IN TRYING TO ASSURE MYSELF OF ADEQUATE WAKE TURB AVOIDANCE; I CONTINUED MY LEFT TURN WELL BEYOND MY ASSIGNED HDG. I WAS STILL WITH THE TWR BEYOND THE END OF THE RWY. WHEN I WAS NOT ASKED TO CONTACT DEP; I INFORMED THE TWR THAT I WAS STILL WITH THEM. WHEN TOLD TO CONTACT DEP; I REALIZED THAT I HAD CONTINUED MY LEFT TURN AND WAS APPROX 90 DEGS BEYOND MY ASSIGNED HDG. IN MY PANIC OVER MY DEVIATION; I WAS UNABLE TO REMEMBER THE DEP FREQ OR THE FACT THAT I HAD WRITTEN IT DOWN ON MY KNEEBOARD AND HAD TO ASK THE TWR FOR THE CORRECT FREQ. I DIDN'T FEEL THAT TURNING BACK TO 020 DEGS WOULD SERVE ANY PURPOSE. WHEN I CONTACTED DEP; THE CTLR INFORMED ME THAT I HAD BEEN ASSIGNED A HDG OF 020 DEGS. I RESPONDED THAT THAT WAS CORRECT AND APOLOGIZED FOR THE MIX UP. THE CTLR STATED THAT THERE WAS TFC W OF ME AND I RESPONDED THAT I HAD THE TFC IN SIGHT. THE REMAINDER OF THE FLT WAS UNEVENTFUL. I HAD ARRIVED AT THE ARPT IN A HURRY TO DEPART SINCE THE MEETING I HAD ATTENDED ALL DAY HAD RUN OVER BY MORE THAN 1 HR. IN ADDITION TO BEING LATE; I WAS ALSO TIRED. I EXPERIENCED MORE THAN THE USUAL DEGREE OF CONCERN OVER WAKE TURB AVOIDANCE SINCE A NASHVILLE PLT RECENTLY WAS APPARENTLY VECTORED INTO WAKE TURB AND CRASHED. THE COMBINATION OF BEING IN A HURRY; BEING TIRED AND THE CIRCUMSTANCES OF BEING EXTREMELY CONCERNED ABOUT A WAKE TURB ENCOUNTER WERE ALL CONTRIBUTING FACTORS IN MY DEVIATION FROM ASSIGNED HDG. HAD I NOT BEEN IN A HURRY; I COULD HAVE ASKED FOR A DELAY TO ALLOW FOR THE WAKE TURB TO DISSIPATE AND I COULD HAVE HAD THE DEP FREQ IN THE #2 RADIO. HAD I NOT BEEN FIXATED ON ONLY 1 THOUGHT (IE; WAKE TURB) I COULD HAVE EASILY REQUESTED A HDG CHANGE FROM THE TWR. I FEEL THE DEVIATION WAS COMPLETELY MY MISTAKE. FORTUNATELY NO SIGNIFICANT EVENT (IE; NEAR MISS) RESULTED. THE FOLLOWING ARE POSSIBLE WAYS TO AVOID A SIMILAR EVENT: 1) DO NOT BE IN A HURRY. 2) DO NOT FLY WHEN TIRED. 3) CONSIDERATION FOR MANDATORY 2-3 MIN HOLD WHEN SMALL ACFT ARE TAKING OFF NEAR LARGER; TRANSPORT SIZE ACFT OR THE ISSUANCE OF DEP VECTORS THAT WILL ASSURE LITTLE OR NO CHANCE FOR WAKE TURB ENCOUNTERS (IE; RIGHT TURN OUT WHEN TAKING OFF FROM A RIGHT PARALLEL RWY. 4) PROMPT HDOF TO DEP SO THAT THE PLT ISN'T LEFT WONDERING WHETHER OR NOT HE HAS BEEN FORGOTTEN.