Narrative:

I had filed an instrument flight plan from houston southwest airport to tupelo, ms. Filed for a hobby five departure (vectors) to beaumont (bpt) VOR then V20 to lake charles. I could not contact clearance delivery on the ground at axh, so I took off VFR and contacted approach control. I was told to fly south while waiting on my clearance. Later approach called back. What I thought the controller said was 'turn left to 90 degree heading, intercept V20, then as filed.' after reading back the clearance I was handed off to another controller. The second controller asked what heading I was flying. I reported I had turned to heading 060 degree to intercept V20. The second controller then told me I was to intercept V70 not V20. It is then that I realized the original assignment of 090 degree heading would have taken directly to an intercept with V70. Possibly my mind was set on intercepting V20 and heard victor 20 instead of victor 70. However, when I check my kneeboard to see how I had copied the clearance, I noticed that I had written V20 then as filed. There were no other contributing factors, the WX was VMC and it was early in the day.

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Original NASA ASRS Text

Title: PLT OF SMA MISHEARS ROUTE CLRNC DUE TO MINDSET AND SIMILAR SOUNDING A/N RESULTING IN HEADING DEVIATION.

Narrative: I HAD FILED AN INSTRUMENT FLT PLAN FROM HOUSTON SW ARPT TO TUPELO, MS. FILED FOR A HOBBY FIVE DEP (VECTORS) TO BEAUMONT (BPT) VOR THEN V20 TO LAKE CHARLES. I COULD NOT CONTACT CLRNC DELIVERY ON THE GND AT AXH, SO I TOOK OFF VFR AND CONTACTED APCH CTL. I WAS TOLD TO FLY S WHILE WAITING ON MY CLRNC. LATER APCH CALLED BACK. WHAT I THOUGHT THE CTLR SAID WAS 'TURN L TO 90 DEG HDG, INTERCEPT V20, THEN AS FILED.' AFTER READING BACK THE CLRNC I WAS HANDED OFF TO ANOTHER CTLR. THE SEC CTLR ASKED WHAT HDG I WAS FLYING. I RPTED I HAD TURNED TO HDG 060 DEG TO INTERCEPT V20. THE SEC CTLR THEN TOLD ME I WAS TO INTERCEPT V70 NOT V20. IT IS THEN THAT I REALIZED THE ORIGINAL ASSIGNMENT OF 090 DEG HDG WOULD HAVE TAKEN DIRECTLY TO AN INTERCEPT WITH V70. POSSIBLY MY MIND WAS SET ON INTERCEPTING V20 AND HEARD VICTOR 20 INSTEAD OF VICTOR 70. HOWEVER, WHEN I CHK MY KNEEBOARD TO SEE HOW I HAD COPIED THE CLRNC, I NOTICED THAT I HAD WRITTEN V20 THEN AS FILED. THERE WERE NO OTHER CONTRIBUTING FACTORS, THE WX WAS VMC AND IT WAS EARLY IN THE DAY.

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.