Narrative:

Air carrier flight from atl to dab. During cruise altitude from atl to dab, about lake city, fl, my copilot had to leave the cockpit for the restroom. About 1 min after he left, we started to get light to moderate CAT. I asked ZJX for flight conditions and got a lower altitude. About this time I turned on the seat belt sign, at same time a flight attendant came up to inquire about the turbulence. The bell rang again for the first officer to come back up. I was making a PA to the passenger regarding the turbulence, i.e., remain seated, etc. During all this, or in the middle of all this, I got a crossing restriction 20 or 30 DME north of crg for FL240. I read back 20 DME and entered it in the FMS descent page. Meanwhile, the copilot is back in the loop and we are descending, passing FL260 for FL240 at 25 DME north of crg. At this time the copilot brings up the point that all month on this leg the crossing restriction was 30 DME, not 20 DME. I agreed with him. We were cleared to the next controller by then and no mention as to the crossing DME. I read back 20 DME, put 20 DME in the FMS but I'm still not sure what was correct.

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Original NASA ASRS Text

Title: CAPT OF ACR MLG ACFT INADVERTENTLY PROGRAMMED THE FMS WITH THE WRONG DME DISTANCE FOR A XING RESTRICTION RESULTING IN NOT COMPLYING WITH THE RESTRICTION.

Narrative: ACR FLT FROM ATL TO DAB. DURING CRUISE ALT FROM ATL TO DAB, ABOUT LAKE CITY, FL, MY COPLT HAD TO LEAVE THE COCKPIT FOR THE RESTROOM. ABOUT 1 MIN AFTER HE LEFT, WE STARTED TO GET LIGHT TO MODERATE CAT. I ASKED ZJX FOR FLT CONDITIONS AND GOT A LOWER ALT. ABOUT THIS TIME I TURNED ON THE SEAT BELT SIGN, AT SAME TIME A FLT ATTENDANT CAME UP TO INQUIRE ABOUT THE TURB. THE BELL RANG AGAIN FOR THE FO TO COME BACK UP. I WAS MAKING A PA TO THE PAX REGARDING THE TURB, I.E., REMAIN SEATED, ETC. DURING ALL THIS, OR IN THE MIDDLE OF ALL THIS, I GOT A XING RESTRICTION 20 OR 30 DME N OF CRG FOR FL240. I READ BACK 20 DME AND ENTERED IT IN THE FMS DSCNT PAGE. MEANWHILE, THE COPLT IS BACK IN THE LOOP AND WE ARE DSNDING, PASSING FL260 FOR FL240 AT 25 DME N OF CRG. AT THIS TIME THE COPLT BRINGS UP THE POINT THAT ALL MONTH ON THIS LEG THE XING RESTRICTION WAS 30 DME, NOT 20 DME. I AGREED WITH HIM. WE WERE CLRED TO THE NEXT CTLR BY THEN AND NO MENTION AS TO THE XING DME. I READ BACK 20 DME, PUT 20 DME IN THE FMS BUT I'M STILL NOT SURE WHAT WAS CORRECT.

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.