Narrative:

We were on the bunts arrival to phl. A crossing restr of 45 mi west of har at FL250 was given. We were currently at FL290. Ordinarily this would be easy to input into the FMS; however; there were 2 fixes between our aircraft and har; both were within the 45 mi range. So the distance between har and fix #1 and fix #2 had to be determined. Both crew members conferred and agreed on where the fix was to be located. And it was placed in the FMS. A few mins later; ATC queried us on our restr. We had intended to comply. We were further asked how far until we reached the fix and the first officer replied 24 mi. We were immediately given a turn and expedited descent. The controller further clarified the initial clearance. Upon review of our fix; it seems that our new fix was inputted off the wrong fix and; therefore; our data was inaccurate. The rest of the flight continued without incident. Both crew used good CRM while flying and verified the clearance as well as what was programmed into the FMS. Both crew were tired as they were already 10 hours into the day; after an overnight of 9 hours of reduced rest. It is my opinion that the crew simply made this mistake due to fatigue during the day and compounded by a short rest period the previous night. A contributing factor was the unusual crossing restr that required the crew to calculate the new fix from its relationship to 2 other; closer fixes. Certainly this incident could be avoided with continued vigilance by the crew; as well as being fully rested before extremely long days. Further problems could be avoided by getting clarification from ATC if there are problems with the clearance restr and potential intermittent fixes.

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Original NASA ASRS Text

Title: CRJ700 CREW MISPROGRAMS XING RESTR IN FMC ON BUNTS STAR INTO PHL.

Narrative: WE WERE ON THE BUNTS ARR TO PHL. A XING RESTR OF 45 MI W OF HAR AT FL250 WAS GIVEN. WE WERE CURRENTLY AT FL290. ORDINARILY THIS WOULD BE EASY TO INPUT INTO THE FMS; HOWEVER; THERE WERE 2 FIXES BTWN OUR ACFT AND HAR; BOTH WERE WITHIN THE 45 MI RANGE. SO THE DISTANCE BTWN HAR AND FIX #1 AND FIX #2 HAD TO BE DETERMINED. BOTH CREW MEMBERS CONFERRED AND AGREED ON WHERE THE FIX WAS TO BE LOCATED. AND IT WAS PLACED IN THE FMS. A FEW MINS LATER; ATC QUERIED US ON OUR RESTR. WE HAD INTENDED TO COMPLY. WE WERE FURTHER ASKED HOW FAR UNTIL WE REACHED THE FIX AND THE FO REPLIED 24 MI. WE WERE IMMEDIATELY GIVEN A TURN AND EXPEDITED DSCNT. THE CTLR FURTHER CLARIFIED THE INITIAL CLRNC. UPON REVIEW OF OUR FIX; IT SEEMS THAT OUR NEW FIX WAS INPUTTED OFF THE WRONG FIX AND; THEREFORE; OUR DATA WAS INACCURATE. THE REST OF THE FLT CONTINUED WITHOUT INCIDENT. BOTH CREW USED GOOD CRM WHILE FLYING AND VERIFIED THE CLRNC AS WELL AS WHAT WAS PROGRAMMED INTO THE FMS. BOTH CREW WERE TIRED AS THEY WERE ALREADY 10 HRS INTO THE DAY; AFTER AN OVERNIGHT OF 9 HRS OF REDUCED REST. IT IS MY OPINION THAT THE CREW SIMPLY MADE THIS MISTAKE DUE TO FATIGUE DURING THE DAY AND COMPOUNDED BY A SHORT REST PERIOD THE PREVIOUS NIGHT. A CONTRIBUTING FACTOR WAS THE UNUSUAL XING RESTR THAT REQUIRED THE CREW TO CALCULATE THE NEW FIX FROM ITS RELATIONSHIP TO 2 OTHER; CLOSER FIXES. CERTAINLY THIS INCIDENT COULD BE AVOIDED WITH CONTINUED VIGILANCE BY THE CREW; AS WELL AS BEING FULLY RESTED BEFORE EXTREMELY LONG DAYS. FURTHER PROBS COULD BE AVOIDED BY GETTING CLARIFICATION FROM ATC IF THERE ARE PROBS WITH THE CLRNC RESTR AND POTENTIAL INTERMITTENT FIXES.

Data retrieved from NASA's ASRS site as of January 2009 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.