Narrative:

Received IFR clearance to fly runway heading after takeoff until reaching the los angeles VOR 315 degree radial; and then to turn right heading 270 degrees. This is the standard IFR departure procedure off of runway 21 at smo. After takeoff; instead of waiting to cross the 315 degree radial before turning to a heading of 270 degrees; I turned right to a heading of 315 degrees upon reaching 400 ft on the initial climb. I knew instinctively that something had gone wrong; although it wasn't immediately obvious to me what it was. When contacted; departure immediately vectored us on a 270 degree heading. Our 315 degree heading had taken us toward higher MVA's and mountains. If ATC had not intervened and if I had not noticed the terrain warnings; this could have had grave consequences; especially at night. I believe this situation occurred because I was sleep deprived. We had flown into smo the night before; but because of the airport curfew; we did not depart until the next day and I had gotten no sleep that night. The clearance we received was not complicated; although it was not communicated with standard phraseology -- that probably played a very minor part in the chain of events; if any. I learned from this experience to be more aware of my own exhaustion when flying. I fly almost exclusively IFR; so there should have been no question in my mind regarding the execution of this clearance.

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Original NASA ASRS Text

Title: A BE-35 PILOT DEVIATED FROM HIS CLEARED COURSE ON DEPT FROM SMO AND WAS HEADED TOWARDS HIGH TERRAIN.

Narrative: RECEIVED IFR CLRNC TO FLY RWY HDG AFTER TKOF UNTIL REACHING THE LOS ANGELES VOR 315 DEG RADIAL; AND THEN TO TURN R HDG 270 DEGS. THIS IS THE STANDARD IFR DEP PROC OFF OF RWY 21 AT SMO. AFTER TKOF; INSTEAD OF WAITING TO CROSS THE 315 DEG RADIAL BEFORE TURNING TO A HDG OF 270 DEGS; I TURNED R TO A HDG OF 315 DEGS UPON REACHING 400 FT ON THE INITIAL CLB. I KNEW INSTINCTIVELY THAT SOMETHING HAD GONE WRONG; ALTHOUGH IT WASN'T IMMEDIATELY OBVIOUS TO ME WHAT IT WAS. WHEN CONTACTED; DEP IMMEDIATELY VECTORED US ON A 270 DEG HDG. OUR 315 DEG HDG HAD TAKEN US TOWARD HIGHER MVA'S AND MOUNTAINS. IF ATC HAD NOT INTERVENED AND IF I HAD NOT NOTICED THE TERRAIN WARNINGS; THIS COULD HAVE HAD GRAVE CONSEQUENCES; ESPECIALLY AT NIGHT. I BELIEVE THIS SITUATION OCCURRED BECAUSE I WAS SLEEP DEPRIVED. WE HAD FLOWN INTO SMO THE NIGHT BEFORE; BUT BECAUSE OF THE ARPT CURFEW; WE DID NOT DEPART UNTIL THE NEXT DAY AND I HAD GOTTEN NO SLEEP THAT NIGHT. THE CLRNC WE RECEIVED WAS NOT COMPLICATED; ALTHOUGH IT WAS NOT COMMUNICATED WITH STANDARD PHRASEOLOGY -- THAT PROBABLY PLAYED A VERY MINOR PART IN THE CHAIN OF EVENTS; IF ANY. I LEARNED FROM THIS EXPERIENCE TO BE MORE AWARE OF MY OWN EXHAUSTION WHEN FLYING. I FLY ALMOST EXCLUSIVELY IFR; SO THERE SHOULD HAVE BEEN NO QUESTION IN MY MIND REGARDING THE EXECUTION OF THIS CLRNC.

Data retrieved from NASA's ASRS site as of May 2009 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.