Narrative:

At 7000 ft, our flight was given traffic at 10 O'clock position and 5 mi at 8000 ft. My first officer called it in sight (I thought I saw it too, but I was looking at a different aircraft). At that point, we were cleared to climb to 14000 ft (and to expedite through 11000 ft while maintaining visual separation from our 10 O'clock position traffic). I started to climb when I saw the actual traffic. We were approximately 3 mi apart when our flight passed through the traffic altitude of 8000 ft and approximately 8400 ft at 2 mi separation. We never received any TCASII warning and the other flight never deviated from their altitude. At the point of convergence, our vertical separation was more than 1000 ft. This was not in anyway a near miss but had we not slowed from 250 KTS to 210 KTS in a hurry (trading altitude for airspeed) our separation would have been a lot less. Both pilots, in a situation like this, should always make sure they are looking at the same traffic. If I had seen the actual traffic initially, I would not have elected to climb until the traffic had passed away from us.

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Original NASA ASRS Text

Title: LESS THAN DESIRED CLRNC BTWN A CLBING ACR AND ANOTHER ACFT LEVEL AT 8000 FT. FLC HAD ACCEPTED A VISUAL SEPARATION CLB.

Narrative: AT 7000 FT, OUR FLT WAS GIVEN TFC AT 10 O'CLOCK POS AND 5 MI AT 8000 FT. MY FO CALLED IT IN SIGHT (I THOUGHT I SAW IT TOO, BUT I WAS LOOKING AT A DIFFERENT ACFT). AT THAT POINT, WE WERE CLRED TO CLB TO 14000 FT (AND TO EXPEDITE THROUGH 11000 FT WHILE MAINTAINING VISUAL SEPARATION FROM OUR 10 O'CLOCK POS TFC). I STARTED TO CLB WHEN I SAW THE ACTUAL TFC. WE WERE APPROX 3 MI APART WHEN OUR FLT PASSED THROUGH THE TFC ALT OF 8000 FT AND APPROX 8400 FT AT 2 MI SEPARATION. WE NEVER RECEIVED ANY TCASII WARNING AND THE OTHER FLT NEVER DEVIATED FROM THEIR ALT. AT THE POINT OF CONVERGENCE, OUR VERT SEPARATION WAS MORE THAN 1000 FT. THIS WAS NOT IN ANYWAY A NEAR MISS BUT HAD WE NOT SLOWED FROM 250 KTS TO 210 KTS IN A HURRY (TRADING ALT FOR AIRSPD) OUR SEPARATION WOULD HAVE BEEN A LOT LESS. BOTH PLTS, IN A SIT LIKE THIS, SHOULD ALWAYS MAKE SURE THEY ARE LOOKING AT THE SAME TFC. IF I HAD SEEN THE ACTUAL TFC INITIALLY, I WOULD NOT HAVE ELECTED TO CLB UNTIL THE TFC HAD PASSED AWAY FROM US.

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.