Narrative:

We were given a clearance which we understood as our previously assigned route (prb--rom--gilro--sjc). Apparently the controller meant direct to gilro (we were south of prb at the time). The basis of the controller's clearance was the fact that we could go direct to an intersection through the use of a mapping mode on our center screen. Although the capability exists, course guidance is a bit problematic in that there is really no way that one can tell if one is straying from course, thus navigating direct is not approved. The controller thought that we could do it legally. This is a result of some pilots out there not knowing the legal limitations and passing that kind of bum information around.

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Original NASA ASRS Text

Title: SMT DID NOT FLY THE ROUTE GIVEN IN THEIR CLRNC.

Narrative: WE WERE GIVEN A CLRNC WHICH WE UNDERSTOOD AS OUR PREVIOUSLY ASSIGNED ROUTE (PRB--ROM--GILRO--SJC). APPARENTLY THE CTLR MEANT DIRECT TO GILRO (WE WERE SOUTH OF PRB AT THE TIME). THE BASIS OF THE CTLR'S CLRNC WAS THE FACT THAT WE COULD GO DIRECT TO AN INTERSECTION THROUGH THE USE OF A MAPPING MODE ON OUR CENTER SCREEN. ALTHOUGH THE CAPABILITY EXISTS, COURSE GUIDANCE IS A BIT PROBLEMATIC IN THAT THERE IS REALLY NO WAY THAT ONE CAN TELL IF ONE IS STRAYING FROM COURSE, THUS NAVIGATING DIRECT IS NOT APPROVED. THE CTLR THOUGHT THAT WE COULD DO IT LEGALLY. THIS IS A RESULT OF SOME PLTS OUT THERE NOT KNOWING THE LEGAL LIMITATIONS AND PASSING THAT KIND OF BUM INFORMATION AROUND.

Data retrieved from NASA's ASRS site as of August 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.