Narrative:

Our flight plan completely ignored traditional fuel use for descent and holding during NOTAM described times of congestion in our destination. Added fuel to what is normal operations requirement at this hour; and we used all of it. Our dispatcher advised our destination was VFR. It was; however; forecast for 700 ft ceilings and we made a 400 ft ILS 27R after delays and holding; all typical of our destination at this hour with the existing weather patterns. No fuel was put onboard by the dispatcher for NOTAM of delays at our hour of arrival or the standard descent fuel burn. We held for the 4th time this month; a 100% hold percentage again.enroute to our destination we get a significant reroute adding about 5;000 burn. We expected this and added fuel not allowed for on the flight plan. 100% reroute percentage to our destination this month. Aircraft IRU stored magnetic variation deviates from the current earth's magnetic properties by approximately 20 years. Aircraft stored magnetic variation data in the irus represents 1990-95 earth magnetic variation. The aircraft software is multiple revisions old. Aircraft nd displayed magnetic course is 6 degrees off the flight plan magnetic course outbound from this waypoint; disallowing a check for reasonable magnetic course numbers vs. Actual magnetic course. Navigation map plotted true course; our flight plan true course and nd course in true are all identical; further indicting the IRU magnetic variable cards as multiple revisions out of date. Check of course reasonableness per ICAO oceanic checklist as devised by the ICAO north atlantic working groups cannot be accomplished within industry standards of 2 degrees. Dr (dead reckoning) navigation in magnetic would be a disaster. No procedures exist to dr in true. Our flight plane fails to provide average courses between waypoints and average drift; both traditional navigation elements removed from the fpf paperwork used for years. Our flight plans makes dr navigation subject to gross errors in crowded airspace. Aircraft irus need current revision software for accurate magnetic variation.

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Original NASA ASRS Text

Title: An air carrier Captain addressed several issues regarding long range fuel planning and outdated Magnetic Variation sources. This data; utilized to provide magnetic headings published on flight plans and programmed into aircraft IRUs; would make dead reckoning navigation problematic.

Narrative: Our flight plan completely ignored traditional fuel use for descent and holding during NOTAM described times of congestion in our destination. Added fuel to what is normal operations requirement at this hour; and we used all of it. Our Dispatcher advised our destination was VFR. It was; however; forecast for 700 FT ceilings and we made a 400 FT ILS 27R after delays and holding; all typical of our destination at this hour with the existing weather patterns. No fuel was put onboard by the Dispatcher for NOTAM of delays at our hour of arrival or the standard descent fuel burn. We held for the 4th time this month; a 100% hold percentage again.Enroute to our destination we get a significant reroute adding about 5;000 burn. We expected this and added fuel not allowed for on the flight plan. 100% reroute percentage to our destination this month. Aircraft IRU stored magnetic variation deviates from the current earth's magnetic properties by approximately 20 years. Aircraft stored magnetic variation data in the IRUs represents 1990-95 earth magnetic variation. The aircraft software is multiple revisions old. Aircraft ND displayed magnetic course is 6 degrees off the flight plan magnetic course outbound from this waypoint; disallowing a check for reasonable magnetic course numbers vs. actual magnetic course. Navigation map plotted true course; our flight plan true course and ND course in true are all identical; further indicting the IRU magnetic variable cards as multiple revisions out of date. Check of course reasonableness per ICAO Oceanic Checklist as devised by the ICAO North Atlantic Working Groups cannot be accomplished within industry standards of 2 degrees. DR (Dead Reckoning) navigation in magnetic would be a disaster. No procedures exist to DR in true. Our flight plane fails to provide average courses between waypoints and average drift; both traditional navigation elements removed from the FPF paperwork used for years. Our flight plans makes DR navigation subject to gross errors in crowded airspace. Aircraft IRUs need current revision software for accurate magnetic variation.

Data retrieved from NASA's ASRS site as of April 2012 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.