Narrative:

We, air carrier X, departed dfw runway 35L with clearance to 10000' heading 360 degrees. Approximately 20 NM north of dfw we were cleared to a heading of 090 degrees to intercept the dfw 078 degree right outbnd on the dallas 6 departure. During further climb to 17000' the controller on frequency 132.85 directed our attention to air carrier Y climbing out at our 1-2 O'clock position. We acquired visual contact and it was obvious we would pass approximately 1000' above and behind on a converging vector. We were cleared to FL230 after calling visual contact with air carrier Y. Passing approximately FL180 we were given a right turn off the 078 degree right to a heading of 120 degrees and immediately return to FL180, air carrier Y appeared to be on a converging vector with us. Air carrier Y leveled at FL190 with a vector insuring a diverging course. My captain had air carrier Y in sight at all times and never came closer than 3 NM. This report is for record only, but it does reinforce basic rules of aviation. Keep the other guy in sight in order to maintain a safe sep. Don't rely on controllers to maintain sep. I suspect air carrier Y was given an intercept vector for 067 degree right on the dallas 6 but was not cleared to do so. He was set up for a converging vector. Supplemental information from acn 80999: we passed abeam air carrier Y approximately 3 NM both climbing through FL180 for FL230. His altitude was verbally called within 500' vertical of ours.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN 2 ACR ACFT. OPERATIONAL ERROR.

Narrative: WE, ACR X, DEPARTED DFW RWY 35L WITH CLRNC TO 10000' HDG 360 DEGS. APPROX 20 NM N OF DFW WE WERE CLRED TO A HDG OF 090 DEGS TO INTERCEPT THE DFW 078 DEG R OUTBND ON THE DALLAS 6 DEP. DURING FURTHER CLB TO 17000' THE CTLR ON FREQ 132.85 DIRECTED OUR ATTN TO ACR Y CLBING OUT AT OUR 1-2 O'CLOCK POS. WE ACQUIRED VISUAL CONTACT AND IT WAS OBVIOUS WE WOULD PASS APPROX 1000' ABOVE AND BEHIND ON A CONVERGING VECTOR. WE WERE CLRED TO FL230 AFTER CALLING VISUAL CONTACT WITH ACR Y. PASSING APPROX FL180 WE WERE GIVEN A RIGHT TURN OFF THE 078 DEG R TO A HDG OF 120 DEGS AND IMMEDIATELY RETURN TO FL180, ACR Y APPEARED TO BE ON A CONVERGING VECTOR WITH US. ACR Y LEVELED AT FL190 WITH A VECTOR INSURING A DIVERGING COURSE. MY CAPT HAD ACR Y IN SIGHT AT ALL TIMES AND NEVER CAME CLOSER THAN 3 NM. THIS RPT IS FOR RECORD ONLY, BUT IT DOES REINFORCE BASIC RULES OF AVIATION. KEEP THE OTHER GUY IN SIGHT IN ORDER TO MAINTAIN A SAFE SEP. DON'T RELY ON CTLRS TO MAINTAIN SEP. I SUSPECT ACR Y WAS GIVEN AN INTERCEPT VECTOR FOR 067 DEG R ON THE DALLAS 6 BUT WAS NOT CLRED TO DO SO. HE WAS SET UP FOR A CONVERGING VECTOR. SUPPLEMENTAL INFO FROM ACN 80999: WE PASSED ABEAM ACR Y APPROX 3 NM BOTH CLBING THROUGH FL180 FOR FL230. HIS ALT WAS VERBALLY CALLED WITHIN 500' VERT OF OURS.

Data retrieved from NASA's ASRS site as of August 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.