Narrative:

Air carrier Y was southwest bound at FL230. I had an air carrier X at lbv at FL240 ready to descent into tpa. I heard my d-side say that they were getting ready to combine the sector which I have not done yet on my own. I then heard him say something that I thought was 'you should get the air carrier X down.' I didn't want to leave a situation for the controller getting my sector so I turned the air carrier Y to the west and have the air carrier X a descent clearance thinking that I had enough time. My d-side then saw the problem and said that I better do something else. I then expedited the air carrier X and turned him to the south. I asked for a report out of FL220. I think that the biggest cause of this error was my lack of experience (1 week checked out at these first two sectors); and the fact that I thought my d-side advised me to do it. Supplemental information from acn 693478: I was working D67 position. The area supervisor instructed us to combine R67 with R46. I initiated handoffs to R46 position. I unplugged from the D67 position to take strip holders to the A46 area. When I returned to the D67 position the R67 controller issued a clearance to air carrier X to descend to FL180. I immediately advised the R67 controller I did not believe separation would be maintained and advised a further vector. The R67 controller immediately turned air carrier X to heading 250 degrees.

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Original NASA ASRS Text

Title: ZMA CTLR EXPERIENCED OPERROR AT FL230 WHEN DESCENDING TFC THROUGH OCCUPIED ALT.

Narrative: ACR Y WAS SOUTHWEST BOUND AT FL230. I HAD AN ACR X AT LBV AT FL240 READY TO DESCENT INTO TPA. I HEARD MY D-SIDE SAY THAT THEY WERE GETTING READY TO COMBINE THE SECTOR WHICH I HAVE NOT DONE YET ON MY OWN. I THEN HEARD HIM SAY SOMETHING THAT I THOUGHT WAS 'YOU SHOULD GET THE ACR X DOWN.' I DIDN'T WANT TO LEAVE A SITUATION FOR THE CTLR GETTING MY SECTOR SO I TURNED THE ACR Y TO THE WEST AND HAVE THE ACR X A DESCENT CLRNC THINKING THAT I HAD ENOUGH TIME. MY D-SIDE THEN SAW THE PROB AND SAID THAT I BETTER DO SOMETHING ELSE. I THEN EXPEDITED THE ACR X AND TURNED HIM TO THE SOUTH. I ASKED FOR A REPORT OUT OF FL220. I THINK THAT THE BIGGEST CAUSE OF THIS ERROR WAS MY LACK OF EXPERIENCE (1 WEEK CHECKED OUT AT THESE FIRST TWO SECTORS); AND THE FACT THAT I THOUGHT MY D-SIDE ADVISED ME TO DO IT. SUPPLEMENTAL INFO FROM ACN 693478: I WAS WORKING D67 POSITION. THE AREA SUPVR INSTRUCTED US TO COMBINE R67 WITH R46. I INITIATED HDOFS TO R46 POSITION. I UNPLUGGED FROM THE D67 POSITION TO TAKE STRIP HOLDERS TO THE A46 AREA. WHEN I RETURNED TO THE D67 POSITION THE R67 CTLR ISSUED A CLRNC TO ACR X TO DESCEND TO FL180. I IMMEDIATELY ADVISED THE R67 CTLR I DID NOT BELIEVE SEPARATION WOULD BE MAINTAINED AND ADVISED A FURTHER VECTOR. THE R67 CTLR IMMEDIATELY TURNED ACR X TO HDG 250 DEGS.

Data retrieved from NASA's ASRS site as of January 2009 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.