Narrative:

I was spacing the B733 behind the E135. I told the E135 to 'keep your speed up' (improper phraseology). He said he'd been assigned 280 KTS previously. I told him to disregard that restr and return to normal or greater, 'the faster, the better.' the B733 was told to reduce to 290 KTS or less, which was about his current speed. The B733 was vectored until he was 6 mi in trail and 30 KTS slower in ground speed than the E135. Then, the B733 was turned back on course. I watched the speeds to make sure they were still working, but then got involved with another aircraft (Z). When conflict alert went off, I saw the E135 had slowed. I reduced the B733's airspeed and turned him again. I then asked the E135 if he was still at 'best forward airspeed.' he replied 'no, we thought you wanted us at 250 KTS at cxr.' that is the standard crossing restr for jets inbound to cle over cxr. I told him 'no, I never gave you that because you're being overtaken by another aircraft. I need you fast.' he replied that he was 'picking it back up.' I believe that although I didn't use correct phraseology on the E135, with the clarification, I made it known that I did not want the E135 slowed. However, with the normal 250 KTS at cxr, many of the pilots have been slowing approaching cxr in anticipation of this restr. It surprised me in this case because I had specifically told this aircraft I wanted him going fast.

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Original NASA ASRS Text

Title: ZOB CTLR ASSUMES E135 PLT UNDERSTANDS WHAT THE CTLR WANTS WHEN A CLRNC WAS ISSUED.

Narrative: I WAS SPACING THE B733 BEHIND THE E135. I TOLD THE E135 TO 'KEEP YOUR SPD UP' (IMPROPER PHRASEOLOGY). HE SAID HE'D BEEN ASSIGNED 280 KTS PREVIOUSLY. I TOLD HIM TO DISREGARD THAT RESTR AND RETURN TO NORMAL OR GREATER, 'THE FASTER, THE BETTER.' THE B733 WAS TOLD TO REDUCE TO 290 KTS OR LESS, WHICH WAS ABOUT HIS CURRENT SPD. THE B733 WAS VECTORED UNTIL HE WAS 6 MI IN TRAIL AND 30 KTS SLOWER IN GND SPD THAN THE E135. THEN, THE B733 WAS TURNED BACK ON COURSE. I WATCHED THE SPDS TO MAKE SURE THEY WERE STILL WORKING, BUT THEN GOT INVOLVED WITH ANOTHER ACFT (Z). WHEN CONFLICT ALERT WENT OFF, I SAW THE E135 HAD SLOWED. I REDUCED THE B733'S AIRSPD AND TURNED HIM AGAIN. I THEN ASKED THE E135 IF HE WAS STILL AT 'BEST FORWARD AIRSPD.' HE REPLIED 'NO, WE THOUGHT YOU WANTED US AT 250 KTS AT CXR.' THAT IS THE STANDARD XING RESTR FOR JETS INBOUND TO CLE OVER CXR. I TOLD HIM 'NO, I NEVER GAVE YOU THAT BECAUSE YOU'RE BEING OVERTAKEN BY ANOTHER ACFT. I NEED YOU FAST.' HE REPLIED THAT HE WAS 'PICKING IT BACK UP.' I BELIEVE THAT ALTHOUGH I DIDN'T USE CORRECT PHRASEOLOGY ON THE E135, WITH THE CLARIFICATION, I MADE IT KNOWN THAT I DID NOT WANT THE E135 SLOWED. HOWEVER, WITH THE NORMAL 250 KTS AT CXR, MANY OF THE PLTS HAVE BEEN SLOWING APCHING CXR IN ANTICIPATION OF THIS RESTR. IT SURPRISED ME IN THIS CASE BECAUSE I HAD SPECIFICALLY TOLD THIS ACFT I WANTED HIM GOING FAST.

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.