Narrative:

MD80 (X) was swbound at FL350. MD80 (Y) was southeast of MD80 (X) about 6 mi behind at FL330 requesting FL350. I had the controller working MD80 (Y) turn him 30 degrees right and slow him down as much as feasible. When MD80 (Y) was switched to my frequency I told him to reduce speed as much as feasible and climb to FL350. When I looked at the speeds a couple of updates later, MD80 (Y) had increased 20 KTS due to the jetstream. Shortly thereafter I turned MD80 (Y) to the left and MD80 (X) to the right and regained my separation.

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Original NASA ASRS Text

Title: ARTCC RADAR CTLR CLBED AN MD80 TO SAME ALT AS ANOTHER MD80 AND HAD LTSS DUE TO SPD DIFFERENTIAL.

Narrative: MD80 (X) WAS SWBOUND AT FL350. MD80 (Y) WAS SE OF MD80 (X) ABOUT 6 MI BEHIND AT FL330 REQUESTING FL350. I HAD THE CTLR WORKING MD80 (Y) TURN HIM 30 DEGS R AND SLOW HIM DOWN AS MUCH AS FEASIBLE. WHEN MD80 (Y) WAS SWITCHED TO MY FREQ I TOLD HIM TO REDUCE SPD AS MUCH AS FEASIBLE AND CLB TO FL350. WHEN I LOOKED AT THE SPDS A COUPLE OF UPDATES LATER, MD80 (Y) HAD INCREASED 20 KTS DUE TO THE JETSTREAM. SHORTLY THEREAFTER I TURNED MD80 (Y) TO THE L AND MD80 (X) TO THE R AND REGAINED MY SEPARATION.

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.