FO OF AN MLG DEVIATED FROM ASSIGNED AIRWAY DUE TO MISINTERP OF THE CHART AIRWAY INDICATOR.

Narrative

FO (PF) MISREAD ENRTE CHART FOR RADIAL OUTBOUND FROM HVQ ON J8 (ASSIGNED). FLEW OUT ON J6 TILL CTR ASKED US WHICH AIRWAY WE WERE ON. LABELS FOR J6 AND J8 ARE VERY CLOSE TO EACH OTHER ON CHART 8/9. ONE OF THESE AIRWAYS SHOULD BE CHANGED. IN A DARK COCKPIT IT IS VERY EASY TO GET THEM CONFUSED ESPECIALLY IF CHART IS DISTORTED. DUE TO EXTREMELY LATE FLT DUE TO WX; MY MIND WAS NOT ON MONITORING HIS NAV; AS HE IS A SUPERB FO AND I HAD COMPLETE CONFIDENCE IN HIS ABILITIES. I HAVE HEARD MANY OTHER FLTS QUERIED ABOUT THIS PROB IN THIS AREA OVER MY 16 YRS IN AIRLINE OPS. I SHOULD HAVE SENT IN THIS FORM FOR THIS A LONG TIME AGO. PLEASE SEE IF FAA CAN CHANGE DESIGNATION OF EITHER J6 OR J8 TO SOMETHING ELSE. ALSO; STUDENT CTLR IN CTR DIDN'T NOTICE OUR ERROR AS SHE WAS VERY BUSY AND DIDN'T MONITOR OUR PROGRESS AS MAYBE SHE (OR HER INSTRUCTOR) COULD HAVE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THAT THE #8 AND #9 CHART TO WHICH HE REFERRED IS A CHART PRODUCED JUST FOR HIS COMPANY. THEREFORE; NO COMPARISON COULD BE MADE TO THE UNITED STATES AND COMMERCIAL MADE ENRTE HIGH ALT CHARTS. HE ADVISED THAT HE WAS GOING TO DISCUSS THIS MATTER WITH THEIR OPS AND SEE IF THE REF TO THE 2 AIRWAYS COULD BE SET APART FURTHER TO REDUCE THE POSSIBILITY OF USING THE WRONG AIRWAY. HE WAS OPERATING A B737-200 TYPE ACFT.