B747-400
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 0; Flight Crew Total 15000; Flight Crew Type 3000
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Other / Unknown; Inflight Event / Encounter CFTT / CFIT
General None Reported / Taken
Aircraft; ATC Equipment / Nav Facility / Buildings; Airport; Procedure; Manuals; Human Factors; Environment - Non Weather Related
Our ANC NOTAM 13/5 disallowed CAT 1; 2 or 3 ILS approaches to minima due to onboard [FMS Navigation Database] magnetic variation in [excessive] deviation from actual airport variation. ANC was nonetheless; listed as intermediate destination. One of our intermediate alternates listed was EDF which has the same magnetic variation problem as ANC yet there are no NOTAMS for EDF prohibiting ILS approaches to CAT 1; 2 or 3 minima.En route in Northwest Canada and Alaska near ANC; the aircraft database variation data for locations deviates from current map variation by up to 8 degrees. Flight crews are; thus; unable to check courses in aircraft vs. flight plan for magnetic accuracy when passing waypoints. As a result; true courses appear to match flight plan true courses while the database magnetic variations appear to be in gross error vs. current navigation maps. Please advise how we are to audit flight plan courses vs. maps.
The reporter was keen to expand on his tribulations in attempting to alert the airlines; the FAA; and even Congress regarding what he believes to be negligence on the part of all parties to maintain current and mutually compatible magnetic variations in the resources flight crews utilize to navigate in higher latitudes: i.e. actual; charted and database utilized variation. He was particularly distressed that they would continue to use (or allow to be used) emergency and alternate airports whose approaches are NOTAM'd as prohibited for use by entire fleets of aircraft for reasons of excessive divergence between these three critical facets which determine the aircraft's flight path when in critical phases of flight close to the ground.The reporter asserts that navigation databases in the affected fleets are not updated for magnetic variation on a regular basis and some approaches (his example was the NDB at BGSF) have differences of as much as eight degrees between actual and published variations which could result in unsafe separation with terrain. He did not comment as to the effect on EGPWS obstacle accuracy which might be similarly compromised by such discrepancies.The reporter asserts he has; over a period of years; approached his company; his union; the chart and equipment manufacturers; and Congress with voluminous amounts of data supporting his concerns to; thus far; no avail. He has personally addressed and has been rebuffed by FAA POIs and airline safety managers on numerous occasions.
A B747-400 Captain reported his airline was using Northern hemisphere airports as enroute re-dispatch destinations and as alternates despite NOTAMs precluding the use of their approaches due to excessive differences between the actual current magnetic variation and those utilized by FMS databases and chart makers.He declared he has been repeatedly rebuffed by all responsible parties in his attempts to ensure that magnetic variations utilized by aircraft navigation databases and aero charts are regularly updated so as to comport to current actual variations. He believes differences at some remote airports are sufficient to result in CFTT or even CFIT events.