Narrative:

Air carrier X was sebnd landing pbi at FL330. Air carrier Y was nwbnd en route to iah at FL310. Air carrier Y cleared direct covia and air carrier X was cleared direct homey. Homey 8. Pbi. With these headings I felt that the acfts were not traffic for each other. I gave air carrier X descent to FL290. I then turned my attention to the non-radar bay and traffic situation. When I looked at the pvd the conflict alert was activated when air carrier X started his descent. I then told air carrier X to climb and maintain FL330 and report reaching. He questioned the clearance and then complied. Sep was lost with the closest proximity 2.2 NM. No evasive action was taken or needed. The situation occurred because my attention was diverted to non-radar bay. Suggestion for preventing the occurrence: the data block reflected FL330 down to FL290. The conflict alert did not activate until the aircraft started to descend. The conflict alert should have been activated as soon as the data block reflexed the assigned altitude FL290. Supplemental information from acn 172288. Were cruising at FL330, when miami center told us to descend to FL290. We were descending at approximately 1500 FPM when center told us to climb to FL330. She did not say 'stop the descent immediately', or 'climb back up to 330', just 'climb to 330.' I told her that she had just given us a descent from FL330, and asked her to verify the altitude assignment of FL330. She simply said 'climb to FL330.' we were descending through approximately 31800' when we got the first call to climb to FL330. By the time we verified the assignment and stopped the descent, we had descended to 31200'. There was no urgency in the controller's voice, so the captain did not violently stop the descent. He just comfortably stopped it when we were told to climb to FL330. As we started our climb, we saw an opp direction air carrier Y go by, off to our right, probably no more than 1/4 mi away. We appeared to be virtually co-altitude. As we climbed through 32000', center again told us to descend to FL290. We asked her to verify the descent clearance, and asked her if we had indeed been given clearance the first time. She did not specifically say we had been given clearance the first time (probably so she would not incriminate herself on tape); she just said something like 'affirmative, descend to FL290.' she made no mention of us leaving an assigned altitude west/O clearance. A call by our chief pilot the next day to miami center verified that the controller was at fault, and that she had been 'disciplined.' the biggest problem I had with her controling was not the fact that we had been given descent clearance with conflicting traffic; it was the fact that there was no urgency on her part to immediately correct the situation. She should have told us to stop the descent immediately, or turned us away from the air carrier Y with a tight turn. The lack of urgency from her did not alert us to any kind of problem, so we were much slower stopping the descent than would have been the case with some urgency in her voice. Passenger comfort would not have been a factor if we were told to do something immediately.

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Original NASA ASRS Text

Title: ACR X HAD LESS THAN STANDARD SEPARATION FROM ACR Y. SYSTEM ERROR.

Narrative: ACR X WAS SEBND LNDG PBI AT FL330. ACR Y WAS NWBND ENRTE TO IAH AT FL310. ACR Y CLRED DIRECT COVIA AND ACR X WAS CLRED DIRECT HOMEY. HOMEY 8. PBI. WITH THESE HDGS I FELT THAT THE ACFTS WERE NOT TFC FOR EACH OTHER. I GAVE ACR X DSNT TO FL290. I THEN TURNED MY ATTN TO THE NON-RADAR BAY AND TFC SITUATION. WHEN I LOOKED AT THE PVD THE CONFLICT ALERT WAS ACTIVATED WHEN ACR X STARTED HIS DSNT. I THEN TOLD ACR X TO CLB AND MAINTAIN FL330 AND RPT REACHING. HE QUESTIONED THE CLRNC AND THEN COMPLIED. SEP WAS LOST WITH THE CLOSEST PROX 2.2 NM. NO EVASIVE ACTION WAS TAKEN OR NEEDED. THE SITUATION OCCURRED BECAUSE MY ATTN WAS DIVERTED TO NON-RADAR BAY. SUGGESTION FOR PREVENTING THE OCCURRENCE: THE DATA BLOCK REFLECTED FL330 DOWN TO FL290. THE CONFLICT ALERT DID NOT ACTIVATE UNTIL THE ACFT STARTED TO DSND. THE CONFLICT ALERT SHOULD HAVE BEEN ACTIVATED AS SOON AS THE DATA BLOCK REFLEXED THE ASSIGNED ALT FL290. SUPPLEMENTAL INFO FROM ACN 172288. WERE CRUISING AT FL330, WHEN MIAMI CTR TOLD US TO DSND TO FL290. WE WERE DSNDING AT APPROX 1500 FPM WHEN CTR TOLD US TO CLB TO FL330. SHE DID NOT SAY 'STOP THE DSNT IMMEDIATELY', OR 'CLB BACK UP TO 330', JUST 'CLB TO 330.' I TOLD HER THAT SHE HAD JUST GIVEN US A DSNT FROM FL330, AND ASKED HER TO VERIFY THE ALT ASSIGNMENT OF FL330. SHE SIMPLY SAID 'CLB TO FL330.' WE WERE DSNDING THROUGH APPROX 31800' WHEN WE GOT THE FIRST CALL TO CLB TO FL330. BY THE TIME WE VERIFIED THE ASSIGNMENT AND STOPPED THE DSNT, WE HAD DSNDED TO 31200'. THERE WAS NO URGENCY IN THE CTLR'S VOICE, SO THE CAPT DID NOT VIOLENTLY STOP THE DSNT. HE JUST COMFORTABLY STOPPED IT WHEN WE WERE TOLD TO CLB TO FL330. AS WE STARTED OUR CLB, WE SAW AN OPP DIRECTION ACR Y GO BY, OFF TO OUR R, PROBABLY NO MORE THAN 1/4 MI AWAY. WE APPEARED TO BE VIRTUALLY CO-ALT. AS WE CLBED THROUGH 32000', CTR AGAIN TOLD US TO DSND TO FL290. WE ASKED HER TO VERIFY THE DSNT CLRNC, AND ASKED HER IF WE HAD INDEED BEEN GIVEN CLRNC THE FIRST TIME. SHE DID NOT SPECIFICALLY SAY WE HAD BEEN GIVEN CLRNC THE FIRST TIME (PROBABLY SO SHE WOULD NOT INCRIMINATE HERSELF ON TAPE); SHE JUST SAID SOMETHING LIKE 'AFFIRMATIVE, DSND TO FL290.' SHE MADE NO MENTION OF US LEAVING AN ASSIGNED ALT W/O CLRNC. A CALL BY OUR CHIEF PLT THE NEXT DAY TO MIAMI CTR VERIFIED THAT THE CTLR WAS AT FAULT, AND THAT SHE HAD BEEN 'DISCIPLINED.' THE BIGGEST PROB I HAD WITH HER CTLING WAS NOT THE FACT THAT WE HAD BEEN GIVEN DSNT CLRNC WITH CONFLICTING TFC; IT WAS THE FACT THAT THERE WAS NO URGENCY ON HER PART TO IMMEDIATELY CORRECT THE SITUATION. SHE SHOULD HAVE TOLD US TO STOP THE DSNT IMMEDIATELY, OR TURNED US AWAY FROM THE ACR Y WITH A TIGHT TURN. THE LACK OF URGENCY FROM HER DID NOT ALERT US TO ANY KIND OF PROB, SO WE WERE MUCH SLOWER STOPPING THE DSNT THAN WOULD HAVE BEEN THE CASE WITH SOME URGENCY IN HER VOICE. PAX COMFORT WOULD NOT HAVE BEEN A FACTOR IF WE WERE TOLD TO DO SOMETHING IMMEDIATELY.

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.