PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Rumours & News (https://www.pprune.org/rumours-news-13/)
-   -   Magnetic change? (https://www.pprune.org/rumours-news/617168-magnetic-change.html)

testpanel 11th Jan 2019 21:49

Magnetic change?
 
Just found this.
Apparently its changing faster.
What to expect?

Airbubba 11th Jan 2019 21:54


Originally Posted by testpanel (Post 10358345)
What to expect?

Someone will figure out a way to tax it...

Herod 11th Jan 2019 22:19


Someone will figure out a way to tax it...
Wasn't that Edison?

Herod 12th Jan 2019 06:48

Polarity switch on its way? Not due...but..

KiloB 12th Jan 2019 07:28

If there is a polarity shift, does it become West Anglia?

Jonty 12th Jan 2019 07:28


Originally Posted by Herod (Post 10358492)
Polarity switch on its way? Not due...but..

its overdue isn’t it?

The Ancient Geek 12th Jan 2019 08:41

Some runways will need to be renumbered but VORs will not change and will be confusing.

Dan_Brown 12th Jan 2019 08:47

This reminds me of a route we flew years ago, overflying Sudan, east/west.. Somewhere between 100 and 200nm west of Khartoum, the standby compass (float type) would give a pronounced dip, in the direction expected, for a duration of about 5mins. IIRC.

All sorts of theories of course amongst the crew(s). but nothing convincing for me, except it had to have been external influence.

DaveReidUK 12th Jan 2019 08:53


Originally Posted by The Ancient Geek (Post 10358553)
Some runways will need to be renumbered but VORs will not change and will be confusing.

What makes you think VOR radials won't change?

The Ancient Geek 12th Jan 2019 09:08

The orientation of VOR antennas is fixed at the time of installation and cannot be changed so the radials refer to the magnetic north which existed when installed.
Note that this refers to the LOCAL magnetic field which may or may not be significantly changed by the magnetic pole wandering as described in the article.

DaveReidUK 12th Jan 2019 09:37


Originally Posted by The Ancient Geek (Post 10358567)
The orientation of VOR antennas is fixed at the time of installation and cannot be changed so the radials refer to the magnetic north which existed when installed.
Note that this refers to the LOCAL magnetic field which may or may not be significantly changed by the magnetic pole wandering as described in the article.

I don't think that's correct. Here's an example of VOR radials that have changed in line with shifted magnetic declination:


https://cimg9.ibsrv.net/gimg/pprune....41f251672e.jpg

KiloB 12th Jan 2019 09:48

Scientists are not just talking about an increasing Variation Drift. Talk is of a sudden 180 deg shift.
It has happened in the past.

safelife 12th Jan 2019 09:56

Why don't we switch to true north navigation, just publish all as true, zero all variation databases in the IRS an be done with it!

Capt Fathom 12th Jan 2019 09:58


Originally Posted by KiloB (Post 10358594)
Scientists are not just talking about an increasing Variation Drift. Talk is of a sudden 180 deg shift.
It has happened in the past.

It has? When?

DaveReidUK 12th Jan 2019 10:03


Originally Posted by Capt Fathom (Post 10358607)
It has? When?

Most recently, about 780,000 years ago.

I don't think that one caused any problem for pilots. :O

Brunhes–Matuyama reversal

Asturias56 12th Jan 2019 10:08

Short term - change in compass declination, repainting work etc

medium term - gradual decline in field strength and more variability

long term - flip - but that may take 500 years - nothing to much to worry about - its happened lots of times since Homo sap. started

eglnyt 12th Jan 2019 10:52


The orientation of VOR antennas is fixed at the time of installation and cannot be changed so the radials refer to the magnetic north which existed when installed.
Note that this refers to the LOCAL magnetic field which may or may not be significantly changed by the magnetic pole wandering as described in the article.
Not the case. All VORs can be adjusted. More modern versions with just the tweak of a screwdriver or the press of a few keys on a laptop, older ones sometimes required large spanners and a hammer. The practice in the UK and most states is to adjust them during flight inspection to minimise the predicted difference over the period to the next expected flight inspection. For DVOR that is 5 years in the UK.

andrasz 12th Jan 2019 11:21

North and South is a Geographical term, referring to the two poles of the earth's rotational axis. In layman's terms, the North is to the left when facing in the direction of the Earth's rotation, and South is to the right. The magnetic poles have simply been named in their relation to the geographical poles. Should the polarity reverse all that needs to be changed is the naming convention, from that moment onwards the former magnetic South becomes North and vica versa, and everything is back to normal.

fox niner 12th Jan 2019 11:42

A pole reversal, or a N/S polarity change, takes a few centuries to stabilize. That is pretty confusing I reckon.

Alpine Flyer 12th Jan 2019 11:49

Avionics-wise we should be able to switch to true north by now but wasn't there something about the magnetic field weakening in conjunction with a flip, thus removing the protection against space radiation for some time....


All times are GMT. The time now is 03:14.


Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.