Narrative:

Cleveland issued altitude, heading and frequency instructions simultaneously. After checking in on the new frequency, we were asked which heading we were flying. We were flying 100 degrees which is what we thought we were assigned. ATC responded that they thought we were issued instructions of 010 degrees. They then amended our descent altitude from FL200 to FL230 instead, and told us that 100 degrees would be okay. There was no apparent conflict. We may have misunderstood 010 degrees as 100 degrees. This report being sent if this is in fact the case. Supplemental information from acn 463771: the sector confirmed with the previous sector that 010 degrees was issued. I don't recall what PNF read back when heading was issued. No conflicts developed.

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Original NASA ASRS Text

Title: CTLR ISSUED 3 ITEMS IN CLRNC AND CREW ONLY DIGESTED 2. THE RESULT WAS A HEADING FLOWN IN ERROR. NO TFC CONFLICT.

Narrative: CLEVELAND ISSUED ALT, HEADING AND FREQ INSTRUCTIONS SIMULTANEOUSLY. AFTER CHKING IN ON THE NEW FREQ, WE WERE ASKED WHICH HEADING WE WERE FLYING. WE WERE FLYING 100 DEGS WHICH IS WHAT WE THOUGHT WE WERE ASSIGNED. ATC RESPONDED THAT THEY THOUGHT WE WERE ISSUED INSTRUCTIONS OF 010 DEGS. THEY THEN AMENDED OUR DSCNT ALT FROM FL200 TO FL230 INSTEAD, AND TOLD US THAT 100 DEGS WOULD BE OKAY. THERE WAS NO APPARENT CONFLICT. WE MAY HAVE MISUNDERSTOOD 010 DEGS AS 100 DEGS. THIS RPT BEING SENT IF THIS IS IN FACT THE CASE. SUPPLEMENTAL INFO FROM ACN 463771: THE SECTOR CONFIRMED WITH THE PREVIOUS SECTOR THAT 010 DEGS WAS ISSUED. I DON'T RECALL WHAT PNF READ BACK WHEN HEADING WAS ISSUED. NO CONFLICTS DEVELOPED.

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.