Narrative:

Before departure in sfo, we were unable to receive our pre departure clearance due to a last min route change. Clearance gave us a new full route clearance. I read back the entire clearance and the controller said 'readback correct.' the captain also was listening and in agreement with the readback and he programmed the FMC accordingly. As backgnd information, I will provide the portion of both rtes where a problem may have occurred. Our flight plan route was: sfo sfo 8 direct lin J84 qbh J10 iow.... Our revised clearance I read back: sfo sfo 8 direct sdy direct FOD J94 pmm.... Departure and climb out were normal. We were given direct to lin as we climbed through FL230. We assumed from lin our route was lin direct sdy. The departure controller asked us how long a flight it was to jfk and I told him 4 hours 55 mins. I also informed him that 4 hours 55 mins was the flight time on our original route however, and now our new route was lin direct sdy FOD J94 pmm, etc and read the rest of the route to him. In a roundabout way, I was asking him to verify our route since the clearance I read back in sfo had not included lin. His lack of response indicated to me that our route was correct. Not that he wasn't listening. We were changed over to ZOA and at approximately 50-75 mi ene of lin the controller said we were off the airway. We told him our clearance was direct sdy. The controller said he showed our clearance lin J84 to sdy. We told him we received our clearance from sfo clearance delivery and had verified the routings with the controller on departure as well. If in fact our clearance was lin J84 to sdy, there were 2 opportunities that controllers could have alerted us to our misunderstanding. Once on the ground in sfo after I had read back the entire full route clearance, and once in the air when I read our entire route of flight to the interested departure controller. Looking back, I would now have specifically asked the controller interested in our flight time who cleared us to lin to verify our route of flight after lin. That would have hopefully cleared up any misunderstanding because both parties would have been actively listening to one another. When in doubt, ask for verification.

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Original NASA ASRS Text

Title: AN ACR FLC FLYING B767 FROM SFO EXPERIENCED CONFUSION AS TO THEIR CLRED RTE TO JFK.

Narrative: BEFORE DEP IN SFO, WE WERE UNABLE TO RECEIVE OUR PDC DUE TO A LAST MIN RTE CHANGE. CLRNC GAVE US A NEW FULL RTE CLRNC. I READ BACK THE ENTIRE CLRNC AND THE CTLR SAID 'READBACK CORRECT.' THE CAPT ALSO WAS LISTENING AND IN AGREEMENT WITH THE READBACK AND HE PROGRAMMED THE FMC ACCORDINGLY. AS BACKGND INFO, I WILL PROVIDE THE PORTION OF BOTH RTES WHERE A PROB MAY HAVE OCCURRED. OUR FLT PLAN RTE WAS: SFO SFO 8 DIRECT LIN J84 QBH J10 IOW.... OUR REVISED CLRNC I READ BACK: SFO SFO 8 DIRECT SDY DIRECT FOD J94 PMM.... DEP AND CLBOUT WERE NORMAL. WE WERE GIVEN DIRECT TO LIN AS WE CLBED THROUGH FL230. WE ASSUMED FROM LIN OUR RTE WAS LIN DIRECT SDY. THE DEP CTLR ASKED US HOW LONG A FLT IT WAS TO JFK AND I TOLD HIM 4 HRS 55 MINS. I ALSO INFORMED HIM THAT 4 HRS 55 MINS WAS THE FLT TIME ON OUR ORIGINAL RTE HOWEVER, AND NOW OUR NEW RTE WAS LIN DIRECT SDY FOD J94 PMM, ETC AND READ THE REST OF THE RTE TO HIM. IN A ROUNDABOUT WAY, I WAS ASKING HIM TO VERIFY OUR RTE SINCE THE CLRNC I READ BACK IN SFO HAD NOT INCLUDED LIN. HIS LACK OF RESPONSE INDICATED TO ME THAT OUR RTE WAS CORRECT. NOT THAT HE WASN'T LISTENING. WE WERE CHANGED OVER TO ZOA AND AT APPROX 50-75 MI ENE OF LIN THE CTLR SAID WE WERE OFF THE AIRWAY. WE TOLD HIM OUR CLRNC WAS DIRECT SDY. THE CTLR SAID HE SHOWED OUR CLRNC LIN J84 TO SDY. WE TOLD HIM WE RECEIVED OUR CLRNC FROM SFO CLRNC DELIVERY AND HAD VERIFIED THE ROUTINGS WITH THE CTLR ON DEP AS WELL. IF IN FACT OUR CLRNC WAS LIN J84 TO SDY, THERE WERE 2 OPPORTUNITIES THAT CTLRS COULD HAVE ALERTED US TO OUR MISUNDERSTANDING. ONCE ON THE GND IN SFO AFTER I HAD READ BACK THE ENTIRE FULL RTE CLRNC, AND ONCE IN THE AIR WHEN I READ OUR ENTIRE RTE OF FLT TO THE INTERESTED DEP CTLR. LOOKING BACK, I WOULD NOW HAVE SPECIFICALLY ASKED THE CTLR INTERESTED IN OUR FLT TIME WHO CLRED US TO LIN TO VERIFY OUR RTE OF FLT AFTER LIN. THAT WOULD HAVE HOPEFULLY CLRED UP ANY MISUNDERSTANDING BECAUSE BOTH PARTIES WOULD HAVE BEEN ACTIVELY LISTENING TO ONE ANOTHER. WHEN IN DOUBT, ASK FOR VERIFICATION.

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.