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Moon The Loon

Degrees True vs Magnetic

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Has anyone any current knowledge on this initiative?

https://www.ainonline.com/aviation-news/aviation-international-news/2013-02-04/nav-canada-proposes-switch-true-north-standard

I've been asking for years "Why are we still using magnetic sources for direction?"

With the ever increasing changes to magnetic poles on our planet (due to the flipping of the core, a once in 500,000 or so year occurrence: http://earthsky.org/earth/earths-magnetic-field-could-flip-within-a-human-lifetime ) including possibly even multiple poles occurring given the rapidity of current changes within the next 50 years, the use of magnetic source for direction seems anachronistic.

GPS/GNSS relies on degrees true changed to degrees magnetic by software.

Why not just leave degrees true alone and use the magnetic compass as a back-up rather than a primary source of direction?

Regulators & NavCan, PLEASE WEIGH IN!

Edited by Moon The Loon

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44 minutes ago, J.O. said:

If the polar flip happens, true vs. magnetic north is the least of our concerns.

Not necessarily. It's already in progress. Our concern should rest on potential affects such as sea level change, tectonic shift, with associated earthquake and volcanic activity. The climate change sham is a deflection. Carbon taxation an even bigger sham.

My question remains: Why magnetic when true references make so much more, and simpler, sense.

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Updating MagVar tables in the IRUs is expensive and differences between charted procedures and FMC generated legs grows over time. Eventually the difference is great enough that one can't fly certain procedures (eg RNAV) in older airplanes (eg 1st generation A320s)...the only reason we used magnetic is because that's all that was available...there's no reason now.

But then again, we could also use plain english in METARS and Forecasts instead of obscure code - as young RCAF pilot trainees, we were told that they had to use codes to shorten the transmission bandwidth in the old teletype days...no more reason for that as far as I can see.

 

 

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If the baseline assumption behind moving away from magnetic navigation is that GNSS is omnipresent and funded forever, then consider what happens if the constellation is degraded.  There are a lot of scenarios where that can happen, some less likely than others, but some based on promises from the US not to dither the signal.  A lot of US promises seem to be getting cancelled lately.....

Vs

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Wikipedia lists a bunch of countries with their own GPS-type systems; Russia, China, India, Japan, the EU, France.  Several of these are regional only and therefore of limited use for aviation and I wouldn't place any bets on getting full, enfettered access to the signal.  Just found it interesting that so many other countries, even those friendly with the USA, would see the need for their own systems.

https://en.wikipedia.org/wiki/Satellite_navigation

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2 hours ago, Vsplat said:

If the baseline assumption behind moving away from magnetic navigation is that GNSS is omnipresent and funded forever, then consider what happens if the constellation is degraded.  There are a lot of scenarios where that can happen, some less likely than others, but some based on promises from the US not to dither the signal.  A lot of US promises seem to be getting cancelled lately.....

Vs

That's kinda my point. For those rare occurrences where GPS/GNSS sources are not available, magnetic direction is the backup.

Consider also that all solar or astro calculations produce true and not magnetic direction finding.

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That's an interesting proposal Moon. I can't come up with anything that favours the use of the magnetic compass. ADF was / is far more useful than a magnetic compass has ever been and it's largely a thing of the past now.

 

 

   

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On 6/25/2018 at 6:45 AM, seeker said:

Wikipedia lists a bunch of countries with their own GPS-type systems; Russia, China, India, Japan, the EU, France.  Several of these are regional only and therefore of limited use for aviation and I wouldn't place any bets on getting full, enfettered access to the signal.  Just found it interesting that so many other countries, even those friendly with the USA, would see the need for their own systems.

https://en.wikipedia.org/wiki/Satellite_navigation

Why have their own system? Freedom from reliance on the US Air Force, most likely. If the Americans ever decide to pull the plug on GPS, it sure is nice to have a backup.

Drastic scenario, I know... but with Trump anything's possible 😕 

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I believed the UK is looking at creating their own GPS network in the event Brexit threatens their access to Gallileo.

If I have it right the US removed the dither on GPS during the first Gulf War as too many things needed the accuracy.

They committed to keep it available to all and sundry but in the age of Trump and those who support him, who knows what promises can be relied on.

 

https://www.gps.gov/policy/

Edited by Innuendo
Add URL.

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Selective availability was removed from the system with the implementation of GPS III according to the website.  This was to appease the civil aviation market.

 

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So then, the guys throwing darts at Trump have demonstrated that they don't know anything about gps systems.

Edited by DEFCON

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it doesnt mean he cant shut it down but if he does he does it for EVERYONE

 

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18 hours ago, Innuendo said:

I believed the UK is looking at creating their own GPS network in the event Brexit threatens their access to Gallileo.

If I have it right the US removed the dither on GPS during the first Gulf War as too many things needed the accuracy.

They committed to keep it available to all and sundry but in the age of Trump and those who support him, who knows what promises can be relied on.

 

https://www.gps.gov/policy/

If I recall, it was GWB and not GHB that removed SA once elected President.

https://www.gps.gov/systems/gps/modernization/sa/

GPS & GLONASS were in their infancy during the first gulf war. Military applications that used GPS prior to removal of SA were exempted from SA.

Once SA was removed by GWB, commercial use of the system exploded with various products ranging from sophisticated nav systems for ships & aircraft to digital watches!

Once again, GPS/GNSS provides True headings. Software is required to convert the true headings to magnetic.

Seems hardly worth the bother.

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I'm not sure what HD might have had to say about Trump's predictability, but we shouldn't forget that it was the HD BOD that set the American icon on the path to bankruptcy long before Trump ever came along. Excuses for their own lack of personal performance and business acumen would be cheap and not worthy of meaningful consideration.

 

Edited by DEFCON

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HDs Business was increasing rapidly before Trump came along.  As a marketing company they are a power house.  There are few if any more recognized brands out there.  Trump has not yet realized that these Tariffs will hurt America far more than anyone else in the end.  just ask Bush.

HD is doing what it needs to do to feed the European and asian markets without being penalized.  Good on them 

 

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Good for them for following the model that says you have to keep growing at all costs to keep investors happy, so with sales declining in the US of course the HD BOD were forced to move production to Thailand where they can continue to grow their European sales numbers using cheap labour etc. ... it all makes me feel like puking. 

And you would blame Trump for HD's soulless capitalistic behaviour?

With that kind of thinking there's no question why Canada is headed down the economic crapper.

 

  

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On ‎6‎/‎28‎/‎2018 at 1:21 PM, boestar said:

HDs Business was increasing rapidly before Trump came along. 

lol, you must be a stringer for CNN....

Harley-Davidson sales decline continues

Tue Jan 30, 2018 - MarketWatch
By Andrew Tangel

Harley-Davidson Inc. on Tuesday reported its fourth straight year of declining sales as the Milwaukee motorcycle maker struggles to get more riders on Hogs.

Harley's motorcycle-related revenue fell 6.8% in 2017 to $4.92 billion, as retail sales continued to suffer in the U.S. and around the globe. Analysts polled by Thomson Reuters had expected revenue of $4.88 billion.

Shares of the company fell 4.7% in premarket trading to $52.70.

Harley-Davidson said its global retail motorcycle sales fell 6.7% in 2017, compared with the prior year, with U.S. sales down 8.5% and international sales declining 3.9%.

Harley said it shipped 144,893 motorcycles in the U.S. in 2017, a drop of 10% from the year before.

Harley-Davidson said it would close its assembly plant in Kansas City and merge its operations into its plant in York, Pa. The company expects to incur restructuring costs of $170 million to $200 million and expects to spend about $75 million in related capital investments over the next two years. After 2020, the company expects the moves to save about $65 million to $75 million of cash annually.

For its fourth quarter, Harley earned $8.3 million, or 5 cents a share, down from $47.2 million, or 27 cents a share, for the same quarter of the prior year.

Results were hurt by a $53.1 million charge related to new tax law and a $29.4 million charge related to a product recall.

Motorcycle revenue in the fourth quarter grew 12% to $1.05 billion.

Harley said it shipped 241,498 motorcycles globally, at the lower end of its guidance of 241,000 to 246,000 motorcycles it had expected. For 2018, Harley-Davidson expects to ship about 231,000 to 236,000 motorcycles globally.

Harley has said it aims to add two million new riders in the U.S. over the coming decade and boost its international business to 50% of its total annual volume from around 38%. The company also is working to expand its appeal to women, minorities, young adults and city dwellers.

As part of that effort, Harley-Davidson said it is on target to launch its first electric motorcycle within 18 months. Tuesday, the company said it would invest more aggressively in developing electric-biking technology.

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6 hours ago, Tango Niner said:

....soooo, back to the original post...

What about all those magnetic RMI's in GA aircraft? Chuck out & replace?

Many can be managed in True. For the rest? Your last comment says it all.

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12 hours ago, Moon The Loon said:

Many can be managed in True. For the rest? Your last comment says it all.

Out with the old... 😁

FWIW I agree, I think with today's equipment it's logical & sensible to do away with magnetic headings.

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