Beechcraft / Beech Aircraft Corp Undifferentiated or Other Model
Confusion; Human-Machine Interface
ATC Issue All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance
Aircraft; Airspace Structure; Human Factors; Procedure
A Beech Bonanza departed RAL on an IFR flight plan. Routing is the ONTN10 routing to SNA. The issue exists when an aircraft puts the route in the box it skips the PDZ 270 radial. I believe this is a known issue and we should stop using clearances that contain radial to airway routes because the box can't get it right. The box [FMS/GPS] omits the part of the route that contains the radial. In this case the clearance should have been PDZ270R..V363.POXKU.V8.SLI; but the box omits the radial and V363 and sends the aircraft PDZ..POXKU.V8.SLI.[I believe we should] stop using clearances that contain radial to airway transitions until this can be fixed.
The reporter advised the ONTN10 is a 'canned' Tower Enroute Control routing that pilots; when thus cleared; may select from their nav database and enter into their GPS/FMS. He has had a number of these events occur in recent years and; as a result; had engaged in communication with this pilot to try to find out why they happen.  In those communications he was advised that the system in use in this case 'populated' the route exactly as it was being flown; having eliminated the large right turn after PDZ followed some 13NM later by a left ~115 degree turn to intercept V363 before proceeding to POXKU.  The result is a much more efficient route from the standpoint of mileage but contrary to the canned route.The reporter advised the 'inefficient' course changes were required due to interference with approaches to other aiports and the MEA on V8-21 between PDZ and SLI.The reporter further advised he had suggested; about two years ago a waypoint; be inserted at the nominal intersection of the PDZ270R and V363 to alter the 'bearing to intercept' leg to become a 'fix to fix' leg which might prove more readily accomodated by FMS/GPS navigation systems.
An SCT TRACON Controller reported a small Beechcraft airplane departing RAL via a standardized 'Tower Enroute Control (TEC)' route; ONTN10 to SNA failed to follow a segment consisting of a radial out of PDZ to intercept V363; instead proceeding via V21-8 to SLI; this event only the last of a number of similar occurrences.