Narrative:

I was on an IFR flight (VMC conditions) from the dallas port airport (klickitat) to boeing field. Route V-112 direct btg, V-23 direct malay intersection, V-23 to seatac VOR/boe. Center diverted me between ltj and btg to the north to intercept V-23 near malay. I arrived at V-23 just or near north of malay. I entered the wrong radial from the seatac VOR. I used the 165 degree radial (V-495) rather than 175 degrees (V-23) which resulted in my being off airway by 10 mi to east, when center advised me. I rechked information and flew to correct radial and proceeded by vectors to boe. No conflict or diversions. Why: I rushed the preflight planning and essentially did it 'on the fly.' I always write everything down, but this was so easy and straight forward, I did it as I went and then as I found myself just north (2 mi) of malay, I hurried and read the wrong radial. Center called attention to my error, but said 'no problem,' but it was not correct.

Google
 

Original NASA ASRS Text

Title: PLT OF A CESSNA 182RG INTERCEPTED THE WRONG VOR RADIAL DURING XCOUNTRY IFR FLT RESULTING IN ARTCC CTLR INTERVENTION AND VECTOR TO ON COURSE.

Narrative: I WAS ON AN IFR FLT (VMC CONDITIONS) FROM THE DALLAS PORT ARPT (KLICKITAT) TO BOEING FIELD. RTE V-112 DIRECT BTG, V-23 DIRECT MALAY INTXN, V-23 TO SEATAC VOR/BOE. CTR DIVERTED ME BTWN LTJ AND BTG TO THE N TO INTERCEPT V-23 NEAR MALAY. I ARRIVED AT V-23 JUST OR NEAR N OF MALAY. I ENTERED THE WRONG RADIAL FROM THE SEATAC VOR. I USED THE 165 DEG RADIAL (V-495) RATHER THAN 175 DEGS (V-23) WHICH RESULTED IN MY BEING OFF AIRWAY BY 10 MI TO E, WHEN CTR ADVISED ME. I RECHKED INFO AND FLEW TO CORRECT RADIAL AND PROCEEDED BY VECTORS TO BOE. NO CONFLICT OR DIVERSIONS. WHY: I RUSHED THE PREFLT PLANNING AND ESSENTIALLY DID IT 'ON THE FLY.' I ALWAYS WRITE EVERYTHING DOWN, BUT THIS WAS SO EASY AND STRAIGHT FORWARD, I DID IT AS I WENT AND THEN AS I FOUND MYSELF JUST N (2 MI) OF MALAY, I HURRIED AND READ THE WRONG RADIAL. CTR CALLED ATTN TO MY ERROR, BUT SAID 'NO PROB,' BUT IT WAS NOT 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.