earth's magnetic field

Is Magnetic entering end-of-life care?

David Learmount , , , , , , , , , , , ,

Results of the ongoing study into how aviation should carry out a transition from using Magnetic North as its navigation heading reference to True North may soon be pre-empted by a geomagnetic cataclysm.

If that sounds a little over-dramatic, it isn’t.

Evidence suggests the chance of a polar reversal of Earth’s magnetic field – a phenomenon known to have happened many millennia ago – may be particularly high right now. But the truth is, no-one knows for sure.

What is known is that, since 1990, the previously gentle migration of Earth’s North Magnetic Pole across the Arctic region of north-eastern Canada has accelerated significantly. Such an acceleration has not been recorded before, so whether this is a precursor to a magnetic polar “flip” is simply not known.

Meanwhile the Polytechnic University of Bucharest’s Faculty of Aerospace Engineering – an observer at the Attitude and Heading Reference Transition Action Group (AHRTAG) – has decided this possibility needs to be investigated, if only to come up with a case study to determine what the world’s navigators would have to do if the “flip” happens before the aviation industry transitions to navigation by True North.

The tentative date for that changeover is 2030. The marine industry is insulated against this problem because it transitioned to navigation by True North in the early 1970s.

Bucharest’s studies so far indicate that a polar reversal, according to geological data about a previous such event, could take place over a period of about 100 years, the poles tipping at a rate of about 3deg per year. Such a rapid polar migration would make the continuing use of the earth’s magnetic field as a heading reference totally impractical.

But no-one knows for sure whether the next “flip” will take as long as 100 years.

With this possibility in mind, it is tempting to re-orientate the studies of bodies like AHRTAG (a working group of the International Association of Institutes of Navigation) – so they move away from persuasion backed by data, and move toward simply agreeing the methodology for a transition to True as soon as possible.

But the plan right now is to continue persuading all the global players – airlines, aircraft manufacturers, avionics manufacturers, airports, air navigation service providers and aviation authorities – to come voluntarily on the journey to the “Mag2True” transition. After all, Bucharest University has not reported – yet – on its polar reversal case study!

Apart from potentially confounding aviators, no-one knows what the terrestrial effects of a magnetic polar reversal could be. Will all seasonally migrating animals, birds and fish be similarly confounded? We don’t know.

Above: a gathering of some of AHRTAG’s members meeting on 5 June at the Royal Institute of Navigation, London, England. At the head of the table on the left is Susan Cheng of Boeing, and to the right is Anthony MacKay of Nav Canada, AHRTAG’s chairman.

Germany studies air navigation fundamentals

David Learmount , , , , , , , , , , , , , , , , , , , ,

Germany’s aviation agency DLR is using a non-stop flight from Hamburg to the Falkland Islands in the far South Atlantic ocean to study the earth’s magnetic field, a navigational resource for aviation and migrating birds alike.

The same flight, operated by Lufthansa using one of its Airbus A350-900s (D-AIXQ), is enabling a crew rotation for scientists working in Antarctic waters in the German research vessel Polarstern.

Lufthansa Airbus A350-900 D-AIXQ is preparing to carry scientists to the South Atlantic

On 30 March Lufthansa’s A350 departs for this, its second non-stop flight on this route, chartered by the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) in Bremerhaven. The first such trip, which took place in February, was the longest non-stop flight a Lufthansa aircraft had ever made – more than 13,000km, with a duration of more than 15h.

This time, the A350 will also be carrying scientists from the German Aerospace Center (Deutschen Zentrums für Luft und Raumfahrt) who will be collecting measurement data to provide further insights on the influence of the Earth’s magnetic field as it affects aviation.

The surface location of the North Magnetic Pole, located at present among the far north-eastern Canadian islands near northern Greenland, is continuing to migrate in the direction of Russian Arctic waters at a faster rate than a few decades ago.

At this rate the magnetic North Pole is expected to pass the geographic North Pole moving in the direction of northern Russia in the next few years. The full significance of this increased rate of changing polarity is not understood, but the earth is – according to scientists – overdue for a polar reversal of its magnetic field. The last polar reversal is believed to have occurred about 750,000 years ago, and although the potential consequences for earth-dwellers are not fully understood, they are believed to be significant – and not only for air navigation.

In fact navigation would be the least of the problems mankind is likely to face. Marine navigation has been based on True North since the early 1970s. Aviation has had the capability to change, but is still plodding on with navigation referenced to the magnetic poles because the industry is reluctant to incur some modest, one-off costs in making the changeover.

“With the second flight to the Falkland Islands, we are not only pleased  to be able to support the AWI’s polar research expedition, but also to make an important contribution to further research into the Earth’s magnetic field,” says Thomas Jahn, Fleet Captain and Falklands Project Manager. “We have already been supporting climate research projects for more than 25 years now.”

The main reason for this second flight to the Falklands is to rotate the Polarstern crew and to pick up the research expedition team. Since the beginning of February, a team of about 50 researchers have been collecting important data on ocean currents, sea ice and the carbon cycle in the Southern Ocean, which, among other things, enable reliable climate predictions.

On 2 April, using flight number LH2575, Lufthansa’s A350 will be bringing AWI’s international research team and the DLR scientists back to Germany. The landing is scheduled for 3:00 p.m. on 3 April at Munich Airport.