Narrative:

Aircraft is based out of napa, was flying empty in VFR conditions on an IFR flight plan, napa to las vegas to pick up vacationers and distribute them about the state. Clearance (to best of my memory) was: cleared to las vegas via direct sgd VOR, right turn (which is the long way around, see figure #1), direct eca VOR as filed. Climb maintain 8000 ft expect FL210 in 10 mins. Takeoff and transition to ZOA on radio was uneventful. Before reaching sgd VOR, center, I thought, changed clearance by saying 'cleared from present position direct eca VOR.' I turned direct to eca VOR which was a left turn and continued on. After about 5 mins center asked me if tower had issued me a right or left turn to eca. I told him my clearance and that's when he cleared me 'direct eca' I assumed he'd voided the right turn. He never really said whether he had or not but said something to the effect of 'we've had some pilots turning left there, we were wondering if the tower had told you. No problem. Climb maintain FL210.' I wouldn't be writing this because it seems like such a small thing that nothing will come out of except the center asking me of my actions makes me think that I violated a clearance. I'm still not convinced I did but wanted to play it safe with this form. If center had issued 'cleared right turn direct eca' obviously no misunderstanding would have occurred. I guess it's a case of 'double assumptions' -- I assumed 'cleared direct' meant shortest turn, center assumed I would stick to my tower issued 'right turn' clearance. WX was great and no other aircraft were around.

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Original NASA ASRS Text

Title: ARTCC CTLR QUESTIONS DIRECTION OF TURN OF ACFT CLBING IN ZOA AIRSPACE.

Narrative: ACFT IS BASED OUT OF NAPA, WAS FLYING EMPTY IN VFR CONDITIONS ON AN IFR FLT PLAN, NAPA TO LAS VEGAS TO PICK UP VACATIONERS AND DISTRIBUTE THEM ABOUT THE STATE. CLRNC (TO BEST OF MY MEMORY) WAS: CLRED TO LAS VEGAS VIA DIRECT SGD VOR, R TURN (WHICH IS THE LONG WAY AROUND, SEE FIGURE #1), DIRECT ECA VOR AS FILED. CLB MAINTAIN 8000 FT EXPECT FL210 IN 10 MINS. TKOF AND TRANSITION TO ZOA ON RADIO WAS UNEVENTFUL. BEFORE REACHING SGD VOR, CTR, I THOUGHT, CHANGED CLRNC BY SAYING 'CLRED FROM PRESENT POS DIRECT ECA VOR.' I TURNED DIRECT TO ECA VOR WHICH WAS A L TURN AND CONTINUED ON. AFTER ABOUT 5 MINS CTR ASKED ME IF TWR HAD ISSUED ME A R OR L TURN TO ECA. I TOLD HIM MY CLRNC AND THAT'S WHEN HE CLRED ME 'DIRECT ECA' I ASSUMED HE'D VOIDED THE R TURN. HE NEVER REALLY SAID WHETHER HE HAD OR NOT BUT SAID SOMETHING TO THE EFFECT OF 'WE'VE HAD SOME PLTS TURNING L THERE, WE WERE WONDERING IF THE TWR HAD TOLD YOU. NO PROB. CLB MAINTAIN FL210.' I WOULDN'T BE WRITING THIS BECAUSE IT SEEMS LIKE SUCH A SMALL THING THAT NOTHING WILL COME OUT OF EXCEPT THE CTR ASKING ME OF MY ACTIONS MAKES ME THINK THAT I VIOLATED A CLRNC. I'M STILL NOT CONVINCED I DID BUT WANTED TO PLAY IT SAFE WITH THIS FORM. IF CTR HAD ISSUED 'CLRED R TURN DIRECT ECA' OBVIOUSLY NO MISUNDERSTANDING WOULD HAVE OCCURRED. I GUESS IT'S A CASE OF 'DOUBLE ASSUMPTIONS' -- I ASSUMED 'CLRED DIRECT' MEANT SHORTEST TURN, CTR ASSUMED I WOULD STICK TO MY TWR ISSUED 'R TURN' CLRNC. WX WAS GREAT AND NO OTHER ACFT WERE AROUND.

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.