Narrative:

Light transport X was proceeding nebound at 17000 crossing the milton 7 arrival route into lga. The high altitude sector handed off medium large transport Y descending to FL190. Medium large transport Y needed to be descended to 13000 (a standard crossing restriction is most often used). At the time medium large transport Y called me I was distracted by a spacing problem elsewhere in my sector. I subsequently issued a standard crossing restriction to medium large transport Y, thinking he was higher than he was. Due to choppy conditions at FL190, medium large transport Y elected to begin his descent right away and vertical separation was lost before lateral separation was achieved. In summary, I made a couple of different errors in this situation. I misinterpreted the radar data block and speed differential of medium large transport Y due to my preoccupation with the other spacing problem in my sector, I made a hasty decision that turned out to be an error in judgement. In the future I will not discontinue my vertical separation until lateral has been completely achieved. I also will try not to take things for granted as much as I seem to lately. (I.e., in most cases, acrs on the milton 7 arrival don't start down right away to make the crossing restriction).

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Original NASA ASRS Text

Title: ARTCC CTLR DSNDED AN MLG THROUGH LTT ALT WITH LTSS.

Narrative: LTT X WAS PROCEEDING NEBOUND AT 17000 XING THE MILTON 7 ARR RTE INTO LGA. THE HIGH ALT SECTOR HANDED OFF MLG Y DSNDING TO FL190. MLG Y NEEDED TO BE DSNDED TO 13000 (A STANDARD XING RESTRICTION IS MOST OFTEN USED). AT THE TIME MLG Y CALLED ME I WAS DISTRACTED BY A SPACING PROB ELSEWHERE IN MY SECTOR. I SUBSEQUENTLY ISSUED A STANDARD XING RESTRICTION TO MLG Y, THINKING HE WAS HIGHER THAN HE WAS. DUE TO CHOPPY CONDITIONS AT FL190, MLG Y ELECTED TO BEGIN HIS DSCNT RIGHT AWAY AND VERT SEPARATION WAS LOST BEFORE LATERAL SEPARATION WAS ACHIEVED. IN SUMMARY, I MADE A COUPLE OF DIFFERENT ERRORS IN THIS SIT. I MISINTERPRETED THE RADAR DATA BLOCK AND SPD DIFFERENTIAL OF MLG Y DUE TO MY PREOCCUPATION WITH THE OTHER SPACING PROB IN MY SECTOR, I MADE A HASTY DECISION THAT TURNED OUT TO BE AN ERROR IN JUDGEMENT. IN THE FUTURE I WILL NOT DISCONTINUE MY VERT SEPARATION UNTIL LATERAL HAS BEEN COMPLETELY ACHIEVED. I ALSO WILL TRY NOT TO TAKE THINGS FOR GRANTED AS MUCH AS I SEEM TO LATELY. (I.E., IN MOST CASES, ACRS ON THE MILTON 7 ARR DON'T START DOWN RIGHT AWAY TO MAKE THE XING RESTRICTION).

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.