Narrative:

MEL 34-39A gbl navigation/gfms inoperative. Automatic route selection to alternate cos-abq selects route 11, navigation system required. As we know, changing navigation code to 'a' in the jr does nothing to the aircraft jdm record indicating RNAV equipment installed. It is installed, it just doesn't work. Dispatcher is responsible to select a routing that is compliant with the restr. To change the routing to alternate turned out to be rather difficult. Fortunately, I had a very senior and very experienced navigation data specialist to assist. I asked to have route 11 made supplemental to inhibit selection. He understood the entire concept, made the change, and further analyzed that control had to clear the fril, as they say, to reset selection. He made that phone call for me, accomplishing the route selection to alternate. This brings up serious questions. I believe the FAA should initiate an investigation as to how many flts have had this deferral with alternate fuel calculated predicated on RNAV routes. The difference on an MD80 between routes 11 and the VOR navigable route 42 is approximately 600-700 pounds. I doubt the 2 or 3 dollars in fuel savings can be shown to make any sense in the cos scenario. It must be faced that this kind of savings would only make sense within the walls of a cpr board room, but not in the actual real world application. It certainly contributes to the known workload in dispatch to have to override these automated functions, especially with a concept so difficult to detect. The certificated airmen, capts and dispatchers are placed in a very compromising situation for the sake of an economic benefit, in this case, an economic benefit that cannot be demonstrated. This should serve to the FAA to expose the dangers inherent within financially distressed air carrier's.

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Original NASA ASRS Text

Title: DISPATCH RPTR IS CONCERNED ABOUT PROPER FLT AND FUEL BURN PLANNING FOR FMS EQUIPPED ACFT WHEN DISPATCHED WITH THE FMS DEFERRED.

Narrative: MEL 34-39A GBL NAV/GFMS INOP. AUTOMATIC RTE SELECTION TO ALTERNATE COS-ABQ SELECTS RTE 11, NAV SYS REQUIRED. AS WE KNOW, CHANGING NAV CODE TO 'A' IN THE JR DOES NOTHING TO THE ACFT JDM RECORD INDICATING RNAV EQUIP INSTALLED. IT IS INSTALLED, IT JUST DOESN'T WORK. DISPATCHER IS RESPONSIBLE TO SELECT A ROUTING THAT IS COMPLIANT WITH THE RESTR. TO CHANGE THE ROUTING TO ALTERNATE TURNED OUT TO BE RATHER DIFFICULT. FORTUNATELY, I HAD A VERY SENIOR AND VERY EXPERIENCED NAV DATA SPECIALIST TO ASSIST. I ASKED TO HAVE RTE 11 MADE SUPPLEMENTAL TO INHIBIT SELECTION. HE UNDERSTOOD THE ENTIRE CONCEPT, MADE THE CHANGE, AND FURTHER ANALYZED THAT CTL HAD TO CLR THE FRIL, AS THEY SAY, TO RESET SELECTION. HE MADE THAT PHONE CALL FOR ME, ACCOMPLISHING THE RTE SELECTION TO ALTERNATE. THIS BRINGS UP SERIOUS QUESTIONS. I BELIEVE THE FAA SHOULD INITIATE AN INVESTIGATION AS TO HOW MANY FLTS HAVE HAD THIS DEFERRAL WITH ALTERNATE FUEL CALCULATED PREDICATED ON RNAV ROUTES. THE DIFFERENCE ON AN MD80 BTWN ROUTES 11 AND THE VOR NAVIGABLE RTE 42 IS APPROX 600-700 LBS. I DOUBT THE 2 OR 3 DOLLARS IN FUEL SAVINGS CAN BE SHOWN TO MAKE ANY SENSE IN THE COS SCENARIO. IT MUST BE FACED THAT THIS KIND OF SAVINGS WOULD ONLY MAKE SENSE WITHIN THE WALLS OF A CPR BOARD ROOM, BUT NOT IN THE ACTUAL REAL WORLD APPLICATION. IT CERTAINLY CONTRIBUTES TO THE KNOWN WORKLOAD IN DISPATCH TO HAVE TO OVERRIDE THESE AUTOMATED FUNCTIONS, ESPECIALLY WITH A CONCEPT SO DIFFICULT TO DETECT. THE CERTIFICATED AIRMEN, CAPTS AND DISPATCHERS ARE PLACED IN A VERY COMPROMISING SIT FOR THE SAKE OF AN ECONOMIC BENEFIT, IN THIS CASE, AN ECONOMIC BENEFIT THAT CANNOT BE DEMONSTRATED. THIS SHOULD SERVE TO THE FAA TO EXPOSE THE DANGERS INHERENT WITHIN FINANCIALLY DISTRESSED ACR'S.

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.