Narrative:

I was holding for IFR release on 20L. The tower had just cleared an small aircraft for takeoff on 20R. Tower asked me if I could maintain visual separation. I responded yes and was cleared for takeoff. Upon reaching approximately 1000 AGL I entered an obscuring layer that I had not observed from the ground and subsequently lost visual contact with the small aircraft. I reported my IMC conditions immediately and was told to make 'a good rate of turn' to a new heading. From the conversation that followed I learned that the small aircraft was also on an IFR clearance. I was not told this initially when asked if I could maintain visual separation and had not been aware of that fact. My suspicion is that we were closer than the required minimum for IFR separation although that was never stated.

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Original NASA ASRS Text

Title: CPR SMT FAILED TO MAINTAIN VISUAL SEPARATION AFTER ACCEPTING A TKOF CLRNC WITH THAT RESTRICTION.

Narrative: I WAS HOLDING FOR IFR RELEASE ON 20L. THE TWR HAD JUST CLRED AN SMA FOR TKOF ON 20R. TWR ASKED ME IF I COULD MAINTAIN VISUAL SEPARATION. I RESPONDED YES AND WAS CLRED FOR TKOF. UPON REACHING APPROX 1000 AGL I ENTERED AN OBSCURING LAYER THAT I HAD NOT OBSERVED FROM THE GND AND SUBSEQUENTLY LOST VISUAL CONTACT WITH THE SMA. I REPORTED MY IMC CONDITIONS IMMEDIATELY AND WAS TOLD TO MAKE 'A GOOD RATE OF TURN' TO A NEW HDG. FROM THE CONVERSATION THAT FOLLOWED I LEARNED THAT THE SMA WAS ALSO ON AN IFR CLRNC. I WAS NOT TOLD THIS INITIALLY WHEN ASKED IF I COULD MAINTAIN VISUAL SEPARATION AND HAD NOT BEEN AWARE OF THAT FACT. MY SUSPICION IS THAT WE WERE CLOSER THAN THE REQUIRED MINIMUM FOR IFR SEPARATION ALTHOUGH THAT WAS NEVER STATED.

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.