MagNav

[CptTrips]

Kinda interesting:

https://www.popularmechanics.com/military/research/a33512412/air-force-magnetic-field-gps/

Who wants to bet we've been flying crazy stealth UAV recon aircraft over all kinds of interesting places at night mapping mag fields.

[Vulcan]

On the same page... https://www.popularmechanics.com/science/environment/a32702425/magnetic-field-anomaly/

[CptTrips]

On the same page... https://www.popularmechanics.com/science/environment/a32702425/magnetic-field-anomaly/

I didn't see that, but I was thinking the same thing.  I've been reading for years that our magnetic poles might be near swapping (which sounds like a bad thing ti me).

Still, I see their point.  Anti-satellite weapons are fairly low tech.  Chinese and Russia would have little trouble taking out our GPS system.  China has already bee blowing up some of their own sats in tests (thanks for the space litter).


 

[save]

As far as taking out opponents satellites, it come both ways.

[FESS67]

When I was in the army we used a map and a compass.  That is all you need.  Sure, GPS makes it easier and more accurate but not essential.

Way back in the day I was on recce for a gun position and I chose a spot.  Another officer came along and told me, based on his new fangled GPS, that I was 500m out and should be over there ---->.  He points to the inside part of a Y formed by 2 small brooks.  Well, firstly, no way am I putting my guns in that bottleneck!  Secondly, you are way out on your navigation!  He does not take kindly to that and argues until I get the map out and ask him to verify his choice.  He went quiet.

GPS is great but at the end of the day, when it comes to it, a map a compass and hopefully a competent person looking at both will still do the job.

[Eagler]

GPS is another luxury one gave up freedom for.

360 is great and scary at the same time

Everyone is now track but at least we know where that amazon package is....

Eagler

[Shuffler]

GPS is another luxury one gave up freedom for.

360 is great and scary at the same time

Everyone is now track but at least we know where that amazon package is....

Eagler

UPS tracking.... great too. USPS.... terrible. LOL


My brother once thought his phone was lost. I got online and told him it was at his home. He had the maid check out in his vette and it had slid out of his jacket pocket and between the passenger door and seat. It can be handy.

[CptTrips]

As far as taking out opponents satellites, it come both ways.

Sure.  But maybe our military has become more dependent on it than others.
I bet our C&C systems would be helpless without GPS.

I wonder how much our pilots ability to pickle dumb bombs with accuracy has degraded?

[CptTrips]

When I was in the army we used a map and a compass.  That is all you need.  Sure, GPS makes it easier and more accurate but not essential.

Way back in the day I was on recce for a gun position and I chose a spot.  Another officer came along and told me, based on his new fangled GPS, that I was 500m out and should be over there ---->.  He points to the inside part of a Y formed by 2 small brooks.  Well, firstly, no way am I putting my guns in that bottleneck!  Secondly, you are way out on your navigation!  He does not take kindly to that and argues until I get the map out and ask him to verify his choice.  He went quiet.

GPS is great but at the end of the day, when it comes to it, a map a compass and hopefully a competent person looking at both will still do the job.

The key function of GPS in the battlespace isn't helping grunts hump the bush.  I reckon they can just shoot an azimuth.

It's the ability to drop ord from beyond AA alt or guide in a cruise missile from 1000km away with pinpoint accuracy.

 

[Ramesis]

I can see how it may be done... I was field engineer for MRI and its basic principle of operation is
that a magnetic field is modified to create a 1-10 mm a slice of the human body whether transverse,
sagittal, coronal or any between... MRI uses 3 gradient currents to determine the orthogonality
of each slice... maybe that is what all the atmospheric testing has been about 

[Vulcan]

The problem is the magnetic field is not consistent, it's lumpy with all sorts of distortions depending on geography and other factors. Here in NZ we have some significant anomalies, to the point where early VR headsets that used a magnetometer for tracking drifted badly making them unusable.

[Shuffler]

I am in Texas and the New Zealanders used to call me the Northern Light. 

[CptTrips]

The problem is the magnetic field is not consistent, it's lumpy with all sorts of distortions depending on geography and other factors. Here in NZ we have some significant anomalies, to the point where early VR headsets that used a magnetometer for tracking drifted badly making them unusable.

What I thought I was getting from the article is that it is those very anomalies that make it possible.  Those variations are like terrain features in the magnetic fields.  As long as they have been mapped ahead of time with with sufficient resolution the guidance system can lock on to those predictable variations and use them as fixes (probably in combination with inertial guidance). 

If the field was perfectly uniform, it would be like navigating on a featureless desert.

[Vulcan]

What I thought I was getting from the article is that it is those very anomalies that make it possible.  Those variations are like terrain features in the magnetic fields.  As long as they have been mapped ahead of time with with sufficient resolution the guidance system can lock on to those predictable variations and use them as fixes (probably in combination with inertial guidance). 

If the field was perfectly uniform, it would be like navigating on a featureless desert.

The anomalies change though, especially if you're on significant fault lines. We have valleys here that sometimes cause a compass to flip or even spin.