Narrative:

The event was deviation from a departure heading after takeoff and loss of separation with another departing aircraft on a parallel runway. I was cleared to depart runway 8R atl on the dawgs.3 SID and climb to 10000 ft. The tower cleared me for takeoff with a heading of 075 degrees after the middle marker. After takeoff I was performing my after takeoff checklist and noticed the middle marker annunciator; I finished the checklist and turned to 075 degree heading. I contacted atl departure and was asked what instructions were given to me by the tower. I said I was given the 075 degree heading after the middle marker. I had noticed another plane that had departed to my right and was at the same altitude; heading in the same direction (east) as me; but slowly getting closer. Departure issued a turn to a heading of 050 degrees. I was asked to call approach when I landed and given a telephone number. After landing; I called and was asked what the tower instructions were again and I stated them again. I was told I didn't turn soon enough and lost separation with the other plane.

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Original NASA ASRS Text

Title: A CE500 TURNED LATE AFTER DEPARTING ATL RWY 8R AND LOST SEPARATION WITH AN ACFT DEPARTING A PARALLEL RWY.

Narrative: THE EVENT WAS DEV FROM A DEP HDG AFTER TKOF AND LOSS OF SEPARATION WITH ANOTHER DEPARTING ACFT ON A PARALLEL RWY. I WAS CLRED TO DEPART RWY 8R ATL ON THE DAWGS.3 SID AND CLB TO 10000 FT. THE TWR CLRED ME FOR TKOF WITH A HDG OF 075 DEGS AFTER THE MIDDLE MARKER. AFTER TKOF I WAS PERFORMING MY AFTER TKOF CHKLIST AND NOTICED THE MIDDLE MARKER ANNUNCIATOR; I FINISHED THE CHKLIST AND TURNED TO 075 DEG HDG. I CONTACTED ATL DEP AND WAS ASKED WHAT INSTRUCTIONS WERE GIVEN TO ME BY THE TWR. I SAID I WAS GIVEN THE 075 DEG HDG AFTER THE MIDDLE MARKER. I HAD NOTICED ANOTHER PLANE THAT HAD DEPARTED TO MY R AND WAS AT THE SAME ALT; HEADING IN THE SAME DIRECTION (E) AS ME; BUT SLOWLY GETTING CLOSER. DEP ISSUED A TURN TO A HDG OF 050 DEGS. I WAS ASKED TO CALL APCH WHEN I LANDED AND GIVEN A TELEPHONE NUMBER. AFTER LNDG; I CALLED AND WAS ASKED WHAT THE TWR INSTRUCTIONS WERE AGAIN AND I STATED THEM AGAIN. I WAS TOLD I DIDN'T TURN SOON ENOUGH AND LOST SEPARATION WITH THE OTHER PLANE.

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.