Narrative:

On takeoff from austin heading 315 degrees assigned (departure runway 31L) and 4000 ft altitude VFR. However thunderstorms in area. Clearance was 315 degree heading, vector to intercept aus 291 degree radial sjt 102 degree radial sjt. The radar suddenly quit and as PNF I began trying to fix the radar -- or trying to get it to work before we went IMC. The PF asked, 'did he clear us to intercept the aus 291 degree radial?' being distraction by talking on the radio and trying to get the radar working, I answered yes and we began a left turn. When departure inquired about the turn, I advised it was my mistake. We were not asked to return to the 315 degree heading, but advised to maintain 4000 ft due to traffic 12 O'clock, 3 mi at 5000 ft. No evasive action was required, we saw them and they saw us.

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Original NASA ASRS Text

Title: CORP JET SUFFERS A HDG TRACK DEV IN PROX OF TSTM ACTIVITY AFTER THEIR WX RADAR EXPERIENCES A MALFUNCTION.

Narrative: ON TKOF FROM AUSTIN HDG 315 DEGS ASSIGNED (DEP RWY 31L) AND 4000 FT ALT VFR. HOWEVER TSTMS IN AREA. CLRNC WAS 315 DEG HDG, VECTOR TO INTERCEPT AUS 291 DEG RADIAL SJT 102 DEG RADIAL SJT. THE RADAR SUDDENLY QUIT AND AS PNF I BEGAN TRYING TO FIX THE RADAR -- OR TRYING TO GET IT TO WORK BEFORE WE WENT IMC. THE PF ASKED, 'DID HE CLR US TO INTERCEPT THE AUS 291 DEG RADIAL?' BEING DISTR BY TALKING ON THE RADIO AND TRYING TO GET THE RADAR WORKING, I ANSWERED YES AND WE BEGAN A L TURN. WHEN DEP INQUIRED ABOUT THE TURN, I ADVISED IT WAS MY MISTAKE. WE WERE NOT ASKED TO RETURN TO THE 315 DEG HDG, BUT ADVISED TO MAINTAIN 4000 FT DUE TO TFC 12 O'CLOCK, 3 MI AT 5000 FT. NO EVASIVE ACTION WAS REQUIRED, WE SAW THEM AND THEY SAW US.

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.