Narrative:

Flight route clearance from mco to clt was orl 340/40, cecil, colliers to join the arrival into clt. There were extensive delays departing mco because of in trail spacing required by ATC due to heavy thunderstorms in the area. After takeoff, we were assigned the 355 degree right of orl. There was a great deal of radio communication on the ATC frequency because of WX avoidance. The direct course to cecil and up or flight planned route would seem to keep us clear of the most intense part of the WX. We were cleared direct to craig J-53 colliers. I read back the clearance and picked up my chart to find craig. When I dialed the craig frequency in I noticed the first officer had turned us toward cecil, approximately 20 degrees left of course. I told him the clearance was craig and he began a turn back toward craig, which was not tuned in to the radios. ATC confirmed the clearance and gave our aircraft, as well as another aircraft, headings to avoid a conflict. ATC later asked if we had cecil tuned and made an initial turn in that direction. I confirmed that this is what appeared had happened. The first officer, when asked, thought we were cleared to cecil, probably because we were just looking at the radar and our flight planned routing for WX clearance. Also, contributing factors could have been the combination of both fixes beginning with 'C' sounding similar and the increased amount of xmissions due to WX avoidance maneuvering. I should have made sure the first officer understood the clearance before going to my chart for the needed information.

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Original NASA ASRS Text

Title: A CLNRC MISINTERP CREATES A LOSS OF SEPARATION BETWEEN TWO ACFT AND CENTER GIVES AN AMENDED CLRNC FOR TRAFFIC.

Narrative: FLT RTE CLRNC FROM MCO TO CLT WAS ORL 340/40, CECIL, COLLIERS TO JOIN THE ARR INTO CLT. THERE WERE EXTENSIVE DELAYS DEPARTING MCO BECAUSE OF IN TRAIL SPACING REQUIRED BY ATC DUE TO HVY TSTMS IN THE AREA. AFTER TKOF, WE WERE ASSIGNED THE 355 DEG R OF ORL. THERE WAS A GREAT DEAL OF RADIO COM ON THE ATC FREQ BECAUSE OF WX AVOIDANCE. THE DIRECT COURSE TO CECIL AND UP OR FLT PLANNED RTE WOULD SEEM TO KEEP US CLR OF THE MOST INTENSE PART OF THE WX. WE WERE CLRED DIRECT TO CRAIG J-53 COLLIERS. I READ BACK THE CLRNC AND PICKED UP MY CHART TO FIND CRAIG. WHEN I DIALED THE CRAIG FREQ IN I NOTICED THE F/O HAD TURNED US TOWARD CECIL, APPROX 20 DEGS L OF COURSE. I TOLD HIM THE CLRNC WAS CRAIG AND HE BEGAN A TURN BACK TOWARD CRAIG, WHICH WAS NOT TUNED IN TO THE RADIOS. ATC CONFIRMED THE CLRNC AND GAVE OUR ACFT, AS WELL AS ANOTHER ACFT, HDGS TO AVOID A CONFLICT. ATC LATER ASKED IF WE HAD CECIL TUNED AND MADE AN INITIAL TURN IN THAT DIRECTION. I CONFIRMED THAT THIS IS WHAT APPEARED HAD HAPPENED. THE F/O, WHEN ASKED, THOUGHT WE WERE CLRED TO CECIL, PROBABLY BECAUSE WE WERE JUST LOOKING AT THE RADAR AND OUR FLT PLANNED RTING FOR WX CLRNC. ALSO, CONTRIBUTING FACTORS COULD HAVE BEEN THE COMBINATION OF BOTH FIXES BEGINNING WITH 'C' SOUNDING SIMILAR AND THE INCREASED AMOUNT OF XMISSIONS DUE TO WX AVOIDANCE MANEUVERING. I SHOULD HAVE MADE SURE THE F/O UNDERSTOOD THE CLRNC BEFORE GOING TO MY CHART FOR THE NEEDED INFO.

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.