Narrative:

I cleared the air carrier Y B737 direct to ape for 2 reasons. I wanted to get him down landing cvg and get him out of the path of the pit departures so I could climb them. I got lower (FL310), he was at FL350, and descended him. I realized there was a potential problem so I planned to watch his rate of descent to see if I needed evasive action or an expedite clearance. Right after I descended the B737, I noticed a situation between 2 aircraft at FL370 being handed off to me. After reviewing both aircraft's route of flight, I had to call the sector handing me these aircraft and tell him to separate them. After numerous attempts to get a hold of this sector, I gave up. Within seconds of hanging up the line, they answered. My assistant asked, 'what do you want to tell them?' so I said I would get the line. After telling them to separate these 2 aircraft, I hung up and was immediately redirected to the B737 and B727 incident because of conflict alert. Unfortunately, conflict alert went off when the aircraft were only 6 mi apart. It was impossible at that point to keep standard separation of 5 mi, but I certainly tried. I expedited the descending aircraft, turned the air carrier X B727 approximately 80 degrees and turned the B737 approximately 50 degrees. The closest they got was 4 mi. One other factor may be that aircraft that don't want to start down into an airport, descend at a very slow rate. I believe this was the case.

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Original NASA ASRS Text

Title: ARTCC RADAR CTLR DSNDED A B737 THROUGH ALT OF B727 WITH LTSS. CTLR KNEW IT WOULD BE TIGHT AND NEEDED TO WATCH THE ACFT CLOSELY, BUT GOT DISTR WITH INTRAFAC COORD. CONFLICT ALERT ACTIVATED, BUT CTLR'S INTERVENTION WAS TOO LATE TO PREVENT A SYS ERROR.

Narrative: I CLRED THE ACR Y B737 DIRECT TO APE FOR 2 REASONS. I WANTED TO GET HIM DOWN LNDG CVG AND GET HIM OUT OF THE PATH OF THE PIT DEPS SO I COULD CLB THEM. I GOT LOWER (FL310), HE WAS AT FL350, AND DSNDED HIM. I REALIZED THERE WAS A POTENTIAL PROB SO I PLANNED TO WATCH HIS RATE OF DSCNT TO SEE IF I NEEDED EVASIVE ACTION OR AN EXPEDITE CLRNC. RIGHT AFTER I DSNDED THE B737, I NOTICED A SIT BTWN 2 ACFT AT FL370 BEING HANDED OFF TO ME. AFTER REVIEWING BOTH ACFT'S RTE OF FLT, I HAD TO CALL THE SECTOR HANDING ME THESE ACFT AND TELL HIM TO SEPARATE THEM. AFTER NUMEROUS ATTEMPTS TO GET A HOLD OF THIS SECTOR, I GAVE UP. WITHIN SECONDS OF HANGING UP THE LINE, THEY ANSWERED. MY ASSISTANT ASKED, 'WHAT DO YOU WANT TO TELL THEM?' SO I SAID I WOULD GET THE LINE. AFTER TELLING THEM TO SEPARATE THESE 2 ACFT, I HUNG UP AND WAS IMMEDIATELY REDIRECTED TO THE B737 AND B727 INCIDENT BECAUSE OF CONFLICT ALERT. UNFORTUNATELY, CONFLICT ALERT WENT OFF WHEN THE ACFT WERE ONLY 6 MI APART. IT WAS IMPOSSIBLE AT THAT POINT TO KEEP STANDARD SEPARATION OF 5 MI, BUT I CERTAINLY TRIED. I EXPEDITED THE DSNDING ACFT, TURNED THE ACR X B727 APPROX 80 DEGS AND TURNED THE B737 APPROX 50 DEGS. THE CLOSEST THEY GOT WAS 4 MI. ONE OTHER FACTOR MAY BE THAT ACFT THAT DON'T WANT TO START DOWN INTO AN ARPT, DSND AT A VERY SLOW RATE. I BELIEVE THIS WAS THE CASE.

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.