Narrative:

When entering flight plan/clearance into FMC, clearance read an airway to dkk, and I misread as drk. At that point FMC dumped the airway and defaulted to direct drk, since drk isn't on the entered airway. First officer and I both checked entered flight plan, but both missed the error. We were both trying to figure out the resulting error in projected fuel at destination when the center controller gave us a vector to intercept the airway in our clearance. Since it was not entered correctly, we turned to intercept the direct course to drk, and we diverged from the cleared airway. Controller caught the deviation almost immediately and gave us direct lhy to return to the airway. We then corrected the FMC and proceeded without further error.

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Original NASA ASRS Text

Title: ACR FLC MAKES ERROR ENTERING NAV INFO IN THE FMS. CTLR CAUGHT ERROR AFTER A TRACK DEV.

Narrative: WHEN ENTERING FLT PLAN/CLRNC INTO FMC, CLRNC READ AN AIRWAY TO DKK, AND I MISREAD AS DRK. AT THAT POINT FMC DUMPED THE AIRWAY AND DEFAULTED TO DIRECT DRK, SINCE DRK ISN'T ON THE ENTERED AIRWAY. FO AND I BOTH CHKED ENTERED FLT PLAN, BUT BOTH MISSED THE ERROR. WE WERE BOTH TRYING TO FIGURE OUT THE RESULTING ERROR IN PROJECTED FUEL AT DEST WHEN THE CTR CTLR GAVE US A VECTOR TO INTERCEPT THE AIRWAY IN OUR CLRNC. SINCE IT WAS NOT ENTERED CORRECTLY, WE TURNED TO INTERCEPT THE DIRECT COURSE TO DRK, AND WE DIVERGED FROM THE CLRED AIRWAY. CTLR CAUGHT THE DEV ALMOST IMMEDIATELY AND GAVE US DIRECT LHY TO RETURN TO THE AIRWAY. WE THEN CORRECTED THE FMC AND PROCEEDED WITHOUT FURTHER ERROR.

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.