Narrative:

My instrument instructor and I were doing approachs and the ATC controller issued us a heading of 040 degrees. I read back 'right 040 degrees, cessna XXX.' a few mins later, the controller said 'cessna XXX, collision alert, make an immediate left to 300 degrees.' my instructor took the plane at that time and turned back to 300 degrees. After this the controller said we were supposed to have stayed at 300 degrees and that he did not tell us to turn to 040 degrees in the first place. I am certain he had told us to turn to 040 degrees. I read it back and my instructor heard it too. I am pretty sure the controller made that mistake.

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Original NASA ASRS Text

Title: C172 SHOOTING PRACTICE APCHS IN IMC RECEIVES COLLISION ALERT FROM STL APCH CTLR AFTER READING BACK AND COMPLYING WITH A HDG CLRNC OF CONTENDED ORIGIN AND OR EXISTENCE.

Narrative: MY INST INSTRUCTOR AND I WERE DOING APCHS AND THE ATC CTLR ISSUED US A HDG OF 040 DEGS. I READ BACK 'R 040 DEGS, CESSNA XXX.' A FEW MINS LATER, THE CTLR SAID 'CESSNA XXX, COLLISION ALERT, MAKE AN IMMEDIATE L TO 300 DEGS.' MY INSTRUCTOR TOOK THE PLANE AT THAT TIME AND TURNED BACK TO 300 DEGS. AFTER THIS THE CTLR SAID WE WERE SUPPOSED TO HAVE STAYED AT 300 DEGS AND THAT HE DID NOT TELL US TO TURN TO 040 DEGS IN THE FIRST PLACE. I AM CERTAIN HE HAD TOLD US TO TURN TO 040 DEGS. I READ IT BACK AND MY INSTRUCTOR HEARD IT TOO. I AM PRETTY SURE THE CTLR MADE THAT MISTAKE.

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.