Narrative:

At approximately 100 NM southwest of fak, inbound to iad, we received a clearance to cross a point (as we heard) 5 mi south of fak at FL270. As per company SOP's, FL270 was set into the altitude alerter box. Simultaneously, the first officer (as per SOP) pointed to the altitude, acknowledging the altitude in the clearance. The 'point,' 5 mi southwest of fak, was loaded into the FMC to display the crossing restr. At 77 NM southwest of fak, the controller asked us to clarify our clearance. I responded, '...cross 5 NM southwest of fak at FL270.' the controller responded, '...the clearance was to cross 85 mi southwest of fak at FL270.' he said that there was no conflict (problem) and to continue descent to FL270 which we accomplished by 75 NM southwest of fak. The flight continued without further incident or comment. Both the first officer and I understood the 5 mi fix. I, as the PNF loaded the 5 NM fix in the FMC. I read back the clearance as 5 NM southwest of fak. The controller acknowledged the readback. As a crew, we performed too many operations to misunderstand the clearance as received. The clearance was not, in itself, an unreasonable request, so there was no reason to question it. There was no outside distraction within the cockpit nor was there any frequency congestion to block any or all of the transmission. My clearance readback was not blocked by another transmission and was acknowledged by the controller. As a crew, we were not at all fatigued or at a high work level. I do not know the condition of the controller, but prior to the issuance of the clearance, I remember the controller discussing a minor conflict in a clearance with another aircraft. After descending to FL270, we were xferred to another frequency where we were issued another clearance. A few mins later, the controller came back and asked us '...if we understood our clearance.' again, I read back the clearance, which this controller acknowledged. This I found to be rather odd, but I didn't bother to question. I'm not sure where the source of the miscom occurred, but I doubt it was in the cockpit.

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Original NASA ASRS Text

Title: LGT CREW WAS GIVEN A CLRNC TO CROSS 5 MI S OF A VOR AT FL270. THEY READ BACK THIS CLRNC TO THE ARTCC RADAR CTLR. AT 77 MI FROM THE VOR THE CTLR SAID THEIR CLRNC WAS TO CROSS 85 MI S AT FL270.

Narrative: AT APPROX 100 NM SW OF FAK, INBOUND TO IAD, WE RECEIVED A CLRNC TO CROSS A POINT (AS WE HEARD) 5 MI S OF FAK AT FL270. AS PER COMPANY SOP'S, FL270 WAS SET INTO THE ALT ALERTER BOX. SIMULTANEOUSLY, THE FO (AS PER SOP) POINTED TO THE ALT, ACKNOWLEDGING THE ALT IN THE CLRNC. THE 'POINT,' 5 MI SW OF FAK, WAS LOADED INTO THE FMC TO DISPLAY THE XING RESTR. AT 77 NM SW OF FAK, THE CTLR ASKED US TO CLARIFY OUR CLRNC. I RESPONDED, '...CROSS 5 NM SW OF FAK AT FL270.' THE CTLR RESPONDED, '...THE CLRNC WAS TO CROSS 85 MI SW OF FAK AT FL270.' HE SAID THAT THERE WAS NO CONFLICT (PROB) AND TO CONTINUE DSCNT TO FL270 WHICH WE ACCOMPLISHED BY 75 NM SW OF FAK. THE FLT CONTINUED WITHOUT FURTHER INCIDENT OR COMMENT. BOTH THE FO AND I UNDERSTOOD THE 5 MI FIX. I, AS THE PNF LOADED THE 5 NM FIX IN THE FMC. I READ BACK THE CLRNC AS 5 NM SW OF FAK. THE CTLR ACKNOWLEDGED THE READBACK. AS A CREW, WE PERFORMED TOO MANY OPS TO MISUNDERSTAND THE CLRNC AS RECEIVED. THE CLRNC WAS NOT, IN ITSELF, AN UNREASONABLE REQUEST, SO THERE WAS NO REASON TO QUESTION IT. THERE WAS NO OUTSIDE DISTR WITHIN THE COCKPIT NOR WAS THERE ANY FREQ CONGESTION TO BLOCK ANY OR ALL OF THE XMISSION. MY CLRNC READBACK WAS NOT BLOCKED BY ANOTHER XMISSION AND WAS ACKNOWLEDGED BY THE CTLR. AS A CREW, WE WERE NOT AT ALL FATIGUED OR AT A HIGH WORK LEVEL. I DO NOT KNOW THE CONDITION OF THE CTLR, BUT PRIOR TO THE ISSUANCE OF THE CLRNC, I REMEMBER THE CTLR DISCUSSING A MINOR CONFLICT IN A CLRNC WITH ANOTHER ACFT. AFTER DSNDING TO FL270, WE WERE XFERRED TO ANOTHER FREQ WHERE WE WERE ISSUED ANOTHER CLRNC. A FEW MINS LATER, THE CTLR CAME BACK AND ASKED US '...IF WE UNDERSTOOD OUR CLRNC.' AGAIN, I READ BACK THE CLRNC, WHICH THIS CTLR ACKNOWLEDGED. THIS I FOUND TO BE RATHER ODD, BUT I DIDN'T BOTHER TO QUESTION. I'M NOT SURE WHERE THE SOURCE OF THE MISCOM OCCURRED, BUT I DOUBT IT WAS IN THE COCKPIT.

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.