Narrative:

I was radar controller at lorain sector. I approved a climb to FL330 on air carrier X that was approximately 10-12 mi from air carrier Y FL330. Both aircraft were on northeast courses, and ground speeds were the same (480 KTS). I noticed air carrier X that was climbing to FL330 was drifting off course, so I asked the controller who was working him if the pilot was on a heading. They said he had been on a vector (which I was not aware of, and I should have been told this). I told the controller to turn air carrier X 20 right so he could get back on course. I was in the process of getting air carrier Y at FL330 on the north side of air carrier X climbing to FL330, because air carrier Y needed to go north of the air carrier X flight path and air carrier X needed to go east and get on the south side of my air carrier Y. The climbing air carrier X speed dropped off 40-50 KTS while my air carrier Y stayed the same. Separation was lost shortly after I asked air carrier X to expedite a climb to FL350 and he informed me that he could not do so because the previous controller had assigned him min cruise for spacing to ewr. I was not told of the reduced airspeed or the vector off course. I did the best I could under known circumstances. Supplemental information from acn 212920: air carrier X issued climb clearance to FL330. Had been assigned preset heading. Air carrier X then reduced to min cruise for spacing. At next controller request, air carrier X turned 20 degrees right. This put air carrier X on converging course with air carrier Y. The speed was not coordinated with the next sector. Initial or subsequent vectors did not sufficiently separate the 2 aircraft.

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Original NASA ASRS Text

Title: ACR X CLB TO OCCUPIED ALT HAD LTSS FROM ACR Y. SYS ERROR. ARTCC INTRAFAC COORD. POTENTIAL CONFLICT.

Narrative: I WAS RADAR CTLR AT LORAIN SECTOR. I APPROVED A CLB TO FL330 ON ACR X THAT WAS APPROX 10-12 MI FROM ACR Y FL330. BOTH ACFT WERE ON NE COURSES, AND GND SPDS WERE THE SAME (480 KTS). I NOTICED ACR X THAT WAS CLBING TO FL330 WAS DRIFTING OFF COURSE, SO I ASKED THE CTLR WHO WAS WORKING HIM IF THE PLT WAS ON A HDG. THEY SAID HE HAD BEEN ON A VECTOR (WHICH I WAS NOT AWARE OF, AND I SHOULD HAVE BEEN TOLD THIS). I TOLD THE CTLR TO TURN ACR X 20 R SO HE COULD GET BACK ON COURSE. I WAS IN THE PROCESS OF GETTING ACR Y AT FL330 ON THE N SIDE OF ACR X CLBING TO FL330, BECAUSE ACR Y NEEDED TO GO N OF THE ACR X FLT PATH AND ACR X NEEDED TO GO E AND GET ON THE S SIDE OF MY ACR Y. THE CLBING ACR X SPD DROPPED OFF 40-50 KTS WHILE MY ACR Y STAYED THE SAME. SEPARATION WAS LOST SHORTLY AFTER I ASKED ACR X TO EXPEDITE A CLB TO FL350 AND HE INFORMED ME THAT HE COULD NOT DO SO BECAUSE THE PREVIOUS CTLR HAD ASSIGNED HIM MIN CRUISE FOR SPACING TO EWR. I WAS NOT TOLD OF THE REDUCED AIRSPD OR THE VECTOR OFF COURSE. I DID THE BEST I COULD UNDER KNOWN CIRCUMSTANCES. SUPPLEMENTAL INFO FROM ACN 212920: ACR X ISSUED CLB CLRNC TO FL330. HAD BEEN ASSIGNED PRESET HDG. ACR X THEN REDUCED TO MIN CRUISE FOR SPACING. AT NEXT CTLR REQUEST, ACR X TURNED 20 DEGS R. THIS PUT ACR X ON CONVERGING COURSE WITH ACR Y. THE SPD WAS NOT COORDINATED WITH THE NEXT SECTOR. INITIAL OR SUBSEQUENT VECTORS DID NOT SUFFICIENTLY SEPARATE THE 2 ACFT.

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.