Narrative:

Upon initial departure from ttn; I missed an instruction from the tower controller to maintain runway heading on climb out. A C206 had departed immediately before me; and was to remain in the airport traffic pattern. As I climbed to altitude; I had the C206 in sight; at 1200 ft MSL I turned south to depart ttn airspace; with the C206 off of my 1 O'clock position; unaware of his intentions. The tower controller asked me if I had traffic at 3 O'clock position; to which I replied negative; not realizing that the controller was referring to the C206. The tower controller then cleared the C206 to downwind; while I climbed to 1500 ft MSL. I had to climb to avoid a dangerous situation with the C206. As it passed under me; the controller asked if I had the traffic; to which I replied 'I did as he passed underneath me.' the controller then said I had ignored traffic reports and that I had ignored an assignment to remain on runway heading. I do not recall hearing ATC telling me to remain runway heading; and ATC gave me a traffic update once. Upon reaching ttn at the conclusion of the flight; I was instructed to call the tower when shutdown; which I did. The controller that answered the telephone relayed a message to me from the tower controller that worked me on takeoff to pay attention to ATC instructions. The cause of this incident was me not hearing the tower controller issue me a heading; which caused a potentially hazardous situation that could have resulted in an airborne collision.

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Original NASA ASRS Text

Title: A C172 PLT AT TNN FAILED TO FOLLOW ATC POST TKOF HDG INSTRUCTIONS AND HAD A NEAR MISS WITH ANOTHER ACFT IN THE PATTERN.

Narrative: UPON INITIAL DEP FROM TTN; I MISSED AN INSTRUCTION FROM THE TWR CTLR TO MAINTAIN RWY HDG ON CLBOUT. A C206 HAD DEPARTED IMMEDIATELY BEFORE ME; AND WAS TO REMAIN IN THE ARPT TFC PATTERN. AS I CLBED TO ALT; I HAD THE C206 IN SIGHT; AT 1200 FT MSL I TURNED S TO DEPART TTN AIRSPACE; WITH THE C206 OFF OF MY 1 O'CLOCK POS; UNAWARE OF HIS INTENTIONS. THE TWR CTLR ASKED ME IF I HAD TFC AT 3 O'CLOCK POS; TO WHICH I REPLIED NEGATIVE; NOT REALIZING THAT THE CTLR WAS REFERRING TO THE C206. THE TWR CTLR THEN CLRED THE C206 TO DOWNWIND; WHILE I CLBED TO 1500 FT MSL. I HAD TO CLB TO AVOID A DANGEROUS SITUATION WITH THE C206. AS IT PASSED UNDER ME; THE CTLR ASKED IF I HAD THE TFC; TO WHICH I REPLIED 'I DID AS HE PASSED UNDERNEATH ME.' THE CTLR THEN SAID I HAD IGNORED TFC RPTS AND THAT I HAD IGNORED AN ASSIGNMENT TO REMAIN ON RWY HDG. I DO NOT RECALL HEARING ATC TELLING ME TO REMAIN RWY HDG; AND ATC GAVE ME A TFC UPDATE ONCE. UPON REACHING TTN AT THE CONCLUSION OF THE FLT; I WAS INSTRUCTED TO CALL THE TWR WHEN SHUTDOWN; WHICH I DID. THE CTLR THAT ANSWERED THE TELEPHONE RELAYED A MESSAGE TO ME FROM THE TWR CTLR THAT WORKED ME ON TKOF TO PAY ATTN TO ATC INSTRUCTIONS. THE CAUSE OF THIS INCIDENT WAS ME NOT HEARING THE TWR CTLR ISSUE ME A HDG; WHICH CAUSED A POTENTIALLY HAZARDOUS SITUATION THAT COULD HAVE RESULTED IN AN AIRBORNE COLLISION.

Data retrieved from NASA's ASRS site as of January 2009 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.