will magnetic navigation ever go away?

exncsurfer

exncsurfer

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I just wanted to throw this topic out there for discussion. Do you think magnetic navigation will ever go away? As in, use True North everywhere, winds, bearings, VOR's, ATC, etc.... Wouldn't this simplify things?

Variation could be an offset dial on the magnetic compass and be mainly a backup to gps based direction.

VOR's would never have to be adjusted for variation fluctuation over time.

Yea, nay, why or why not.
 
I can't see a compelling reason to force everyone to remove the magnetic compass and buy a much more expensive true heading device, so long as the polarity of the earth's magnetic field doesn't switch frequently. It is a cheap, easy to interpret backup device. Let's keep it.

-Skip
 
Skip Miller said:
I can't see a compelling reason to force everyone to remove the magnetic compass and buy a much more expensive true heading device, so long as the polarity of the earth's magnetic field doesn't switch frequently. It is a cheap, easy to interpret backup device. Let's keep it.

-Skip
Click to expand...
Yea, I get why its primary now, but isn't it just as easy to add/subract 7,9,10, or whatever, before using your heading with ATC?
 
Won't say no, but history and investment to date tells me isn't likely. When you take into account almost every form of navigation uses magnetic it just doesn't seem likely to me. Cel Nav didn't replace it, and any nav source that relies on some type of power has to have a backup when it fails.

Just converting to true and dialing in a mag var doesn't change the underlying fact that the compass is still operating on a a magnetic principle, the display is all that's adjusted.
 
It would SUCK to be flying around airspace with lots of people making 26 deg heading errors in response to vectors. True heading is vulnerable to sign error.
 
MAKG1 said:
It would SUCK to be flying around airspace with lots of people making 26 deg heading errors in response to vectors. True heading is vulnerable to sign error.
Click to expand...
Can you explain this a bit, I don't get what you're saying.
 
exncsurfer said:
Can you explain this a bit, I don't get what you're saying.
Click to expand...

In other words, if someone is correcting for magnetic deviation and mistakenly subtracts 13 degrees, instead of adding it then you will have a 26 degree error.

It is confusing. Back in the day when we used DMA quad maps for land navigation, I always went by the graphic when correcting for magnetic deviation as the signage is easy to screw up. Then again, we didn't use true north either, we used grid north.
 
Maybe we will switch to RADIANS! (2 pi radians = 360 degrees). Its METRIC!
 
Use mils, much more precise than regular old radians.
 
Sac Arrow said:
In other words, if someone is correcting for magnetic deviation and mistakenly subtracts 13 degrees, instead of adding it then you will have a 26 degree error.

It is confusing. Back in the day when we used DMA quad maps for land navigation, I always went by the graphic when correcting for magnetic deviation as the signage is easy to screw up. Then again, we didn't use true north either, we used grid north.
Click to expand...
Yea, well I was thinking that this would be mostly automated. Even a manual adjustment on the whiskey compass that you rotate, similar to setting your altimeter with the day's pressure. Then everything you're looking at is true, or close. I guess you're talking about legacy gear and people still using it. I'm just wondering way into the future, would it make sense for True to be primary.

The whole plus minus thing goes away.
 
exncsurfer said:
I just wanted to throw this topic out there for discussion. Do you think magnetic navigation will ever go away? As in, use True North everywhere, winds, bearings, VOR's, ATC, etc.... Wouldn't this simplify things?

Variation could be an offset dial on the magnetic compass and be mainly a backup to gps based direction.

VOR's would never have to be adjusted for variation fluctuation over time.

Yea, nay, why or why not.
Click to expand...

Ever is a long time, but the VORs will be all gone in 20 years. 306 VORs are being decommissioned by 2025.
 
Mills are based on radians. Take 2 pi radians (6.2832) and it by 1000 and you have a mil. (There are 6283 mils in 360 degrees).

BTW. Did you know that at the equator, one minute of angle equals One Nautical Mile? True of all lines of longitude also.
360 degrees x 60 minutes/degree = 21600. 21600 is the circumference of the earth in nautical miles AND the number of minutes in a circle.
 
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exncsurfer said:
Yea, well I was thinking that this would be mostly automated. Even a manual adjustment on the whiskey compass that you rotate, similar to setting your altimeter with the day's pressure. Then everything you're looking at is true, or close. I guess you're talking about legacy gear and people still using it. I'm just wondering way into the future, would it make sense for True to be primary.

The whole plus minus thing goes away.
Click to expand...

The problem with that is you, or your compass, has to know where you are when you set it. That's fine and dandy if you're sitting on the ground parked over the compass rose with a painted true north indication, and you go for a local flight, but if you take a long flight, particularly east or west, you could be off by a few degrees.
 
Sac Arrow said:
The problem with that is you, or your compass, has to know where you are when you set it. That's fine and dandy if you're sitting on the ground parked over the compass rose with a painted true north indication, and you go for a local flight, but if you take a long flight, particularly east or west, you could be off by a few degrees.
Click to expand...
Right, but if GPS or automated True (derived somehow accurately and automatically) was primary, the whiskey compass adjustment could be for backup purposes only and given out by ATC like altimeter adjustments are now.(or otherwise retired)
 
I will always have a magnetic compass in the planes I fly.

I think I posted about this event when it happened, last summer.
I was flying between DXR and O1C for no reason other than to go there.
Being a belt and suspenders kind of guy, I did the paper map thing, plotted some VOR stuff, found some AM radio stations along the way for the ADF, and programed the flight into Avare on my tablet, my phone, and the Garmin system in the plane.
About 40 minutes into the flight, the Garmin reported "GPS Signal Lost" or whatever it is that it says.
"How weird." says I.
I pull out the tablet, and it also says "No GPS"
So I pull out my phone. Same thing.
So I reach over and pull out my stack of paper, and start flying the compass. The magnetic compass. Just because.
Now, if this was to be a GREAT story, I would say that the compass started spinning and a bright light enveloped the airplane and I was abducted by space aliens (as opposed to the guys who cut people's grass).
But the truth is I flew the compass for another 30 odd minutes, clocking times and checkpoints, when suddenly the the magenta line reappeared on the Garmin.

The really weird part of the day was that at least one other pilot I talked to had the same problem, but I could not find ANYTHING official about the interruption of service.
 
exncsurfer said:
Right, but if GPS or automated True (derived somehow accurately and automatically) was primary, the whiskey compass adjustment could be for backup purposes only and given out by ATC like altimeter adjustments are now.(or otherwise retired)
Click to expand...

"Cessna two yankee golf, set compass at deviation of minus ten degrees."

"Um, approach, uh, do I add that or subtract?"

"Hold on a minute. Let me see if I can figure.... Cessna two yankee golf, unable to continue with flight following. Squawk VFR and have a good day."
 
Shepherd said:
I will always have a magnetic compass in the planes I fly.

I think I posted about this event when it happened, last summer.
I was flying between DXR and O1C for no reason other than to go there.
Being a belt and suspenders kind of guy, I did the paper map thing, plotted some VOR stuff, found some AM radio stations along the way for the ADF, and programed the flight into Avare on my tablet, my phone, and the Garmin system in the plane.
About 40 minutes into the flight, the Garmin reported "GPS Signal Lost" or whatever it is that it says.
"How weird." says I.
I pull out the tablet, and it also says "No GPS"
So I pull out my phone. Same thing.
So I reach over and pull out my stack of paper, and start flying the compass. The magnetic compass. Just because.
Now, if this was to be a GREAT story, I would say that the compass started spinning and a bright light enveloped the airplane and I was abducted by space aliens (as opposed to the guys who cut people's grass).
But the truth is I flew the compass for another 30 odd minutes, clocking times and checkpoints, when suddenly the the magenta line reappeared on the Garmin.

The really weird part of the day was that at least one other pilot I talked to had the same problem, but I could not find ANYTHING official about the interruption of service.
Click to expand...
OK, so the moral of your story is the alternatives are not reliable enough now. But, if your compass had a manual variation knob that was set(or your brain was programmed to convert and report True as needed), your scenario could have still been planned and performed using True, no?
 
Clip4 said:
Ever is a long time, but the VORs will be all gone in 20 years. 306 VORs are being decommissioned by 2025.
Click to expand...

No they won't. The FAA is retaining a Minimum Operating Network of VORs as a backup to GPS. When it is complete, the MON will provide a VOR within 100 miles for planes at 5000agl and above. They will be identified as MON on charts.

Bob
 
Sac Arrow said:
"Cessna two yankee golf, set compass at deviation of minus ten degrees."

"Um, approach, uh, do I add that or subtract?"

"Hold on a minute. Let me see if I can figure.... Cessna two yankee golf, unable to continue with flight following. Squawk VFR and have a good day."
Click to expand...
heck, put the +/- in the window, idiot proof as much as possible.
bobmrg said:
No they won't. The FAA is retaining a Minimum Operating Network of VORs as a backup to GPS. When it is complete, the MON will provide a VOR within 100 miles for planes at 5000agl and above. They will be identified as MON on charts.

Bob
Click to expand...
VOR or not, doesn't factor into my hypothetical, the VOR can be calibrated with True directions.
 
bobmrg said:
No they won't. The FAA is retaining a Minimum Operating Network of VORs as a backup to GPS. When it is complete, the MON will provide a VOR within 100 miles for planes at 5000agl and above. They will be identified as MON on charts.

Bob
Click to expand...

And where does the FAA say how long they are going to do this? The OP asked for a prediction of the future. My prediction is all VORs are gone in 20 years.
 
Sounds like a solution in search of a problem. While you're at it, set altimeters at zero for field elevation at every airport so you don't have to calculate AGL, and set clocks by the sun -- straight up is noon.

"East is least and west is best."
True +/- Variation = Magnetic +/- Deviation = Compass (T +/- V = M +/- D = C, or "True Virgins Make Dull Company" or "The Vagrant Moved Down California"; or in reverse, "Can Dead Men Vote Twice" or "Can Ducks Make Vertical Turns".
 
Let me pose a different question. Should we do away with true directions? Couldn't everything be magnetic, and thus no need to account for deviation?
 
Sadly some think we need backup to the backup to the backup although no one can point to anyone being 'saved' by having a mag compass in their planes (despite EVERY plane having one). But we may get a solid state compass replacement that automatically makes the deviation adjustments and a digital readout to boot. After the NextGen sats are all flying we will finally be able to get rid of radar and VORs.
 
I have to admit, this isn't something I think of and maybe I should start thinking about it again before I go on another cross country that goes very far to the E or W.

My local correction for magnetic-true is 1W. Being that it's 1, it's effectively a non-difference.
 
Mtns2Skies said:
Let me pose a different question. Should we do away with true directions? Couldn't everything be magnetic, and thus no need to account for deviation?
Click to expand...

Only if you can tell the earth to rotate on a different axis.

Latitude and longitude are defined in terms of the earth's rotation axis.

Before you say to go and define them differently, magnetic variation changes far more rapidly than some people realize. It would be a problem if every feature on your chart had to be recharted every 5 years, rather than just a few runway numbers here and there.
 
citizen5000 said:
Sadly some think we need backup to the backup to the backup although no one can point to anyone being 'saved' by having a mag compass in their planes (despite EVERY plane having one). But we may get a solid state compass replacement that automatically makes the deviation adjustments and a digital readout to boot. After the NextGen sats are all flying we will finally be able to get rid of radar and VORs.
Click to expand...

NO ONE?

There is an example a few posts up.

I've also had a "solid state" heading reading screw up HSI and GPS displays, and had to fly the mag compass out of IMC. That would have been a real bad place without the mag compass.

I think you've demonstrated in the past that you don't understand that some GPS vulnerabilities affect ALL GPS receivers at the same time. Shepherd's example could be explained by some ***hole trucker below who doesn't want to be caught going someplace he shouldn't, and deploying a jammer.

The usefulness of the mag compass is that it's dirt simple and doesn't depend on anything else in the airplane. It even works with a total electrical power failure.
 
MAKG1 said:
Only if you can tell the earth to rotate on a different axis.

Latitude and longitude are defined in terms of the earth's rotation axis.

Before you say to go and define them differently, magnetic variation changes far more rapidly than some people realize. It would be a problem if every feature on your chart had to be recharted every 5 years, rather than just a few runway numbers here and there.
Click to expand...

Plus the earth's magnetic poles are not antipodal, so it wouldn't work to rotate the earth about its magnetic poles anyway.
 
Mtns2Skies said:
Let me pose a different question. Should we do away with true directions? Couldn't everything be magnetic, and thus no need to account for deviation?
Click to expand...
well....that would work in some places....but, not many. :D
 
exncsurfer said:
OK, so the moral of your story is the alternatives are not reliable enough now. But, if your compass had a manual variation knob that was set(or your brain was programmed to convert and report True as needed), your scenario could have still been planned and performed using True, no?
Click to expand...

Actually if any moral is implied at all, it's that some old technology is better than no technology.
When I fly using a magnetic compass, I don't even look at the numbers on the compass placard. My checkpoints are so close together, I correct my course at every checkpoint. It doesn't matter if you calculate true or magnetic, the error is small and the corrections are constant.
Not the most efficient way to get anywhere, but I don't have actually to be anywhere, so close enough for government work is close enough.
In the interests of full disclosure: I was a lot more anal about it when I was getting paid to fly. Now, not so much.
 
MAKG1 said:
Only if you can tell the earth to rotate on a different axis.

Latitude and longitude are defined in terms of the earth's rotation axis.

Before you say to go and define them differently, magnetic variation changes far more rapidly than some people realize. It would be a problem if every feature on your chart had to be recharted every 5 years, rather than just a few runway numbers here and there.
Click to expand...
Hey, there is another benefit of using True everywhere, runway numbers would never change.
 
MAKG1 said:
...
The usefulness of the mag compass is that it's dirt simple and doesn't depend on anything else in the airplane. It even works with a total electrical power failure.
Click to expand...

Use of true vs. magnetic wouldn't negate the usefulness of having the mag compass or its usefulness, you'd just have to remember the variation in the event that you had to fall back on it when all else fails.
 
exncsurfer said:
Use of true vs. magnetic wouldn't negate the usefulness of having the mag compass or its usefulness, you'd just have to remember the variation in the event that you had to fall back on it when all else fails.
Click to expand...

And everyone would be making 26 degree errors.

What problem are you trying to solve? You're introducing a big one to deal with it, so perhaps it might be a good idea to spell out the goal.
 
MAKG1 said:
And everyone would be making 26 degree errors.

What problem are you trying to solve? You're introducing a big one to deal with it, so perhaps it might be a good idea to spell out the goal.
Click to expand...
Not really trying to solve any problem. Just wondering if magnetic directions will be relevant when higher tech navigation is everywhere.

I don't see how your 26 degree issue would be an issue if a new system is taught and understood by everyone. Now, that same guy is just making is 26 degree errors on his paper nav logs.
 
exncsurfer said:
Not really trying to solve any problem. Just wondering if magnetic directions will be relevant when higher tech navigation is everywhere.

I don't see how your 26 degree issue would be an issue if a new system is taught and understood by everyone. Now, that same guy is just making is 26 degree errors on his paper nav logs.
Click to expand...

Most people don't put vectors on their nav logs. That's where it becomes a real problem. Errors of that magnitude smush people into mountains.

Technology doesn't solve all problems. For redundancy, data-flow is your enemy. You need as little as possible, or you make single point failures that don't need to be.

And if there is no problem to solve, it's mental masturbation. You don't change equipment on every aircraft without some reason to do it.

Technology will never make the earth rotate on a different axis. Nor will it make the magnetic field nicer or less mobile.
 
We could use true. Just set your DG to true. Have the GPS tell you what the declination is all the time. The GPS knows where you are and it looks up the declination at that point. Approach plates are oriented to True. So are VFR charts. A lot things would have to be changed. The changing of it all is what the problem is. And pilots would have to change.

Sort of like changing to the metric system.
 
The best defense against CFIT is having Terrain Warning (TAWS) with Terrain Awareness (color coding) in the cockpit.
 
citizen5000 said:
The best defense against CFIT is having Terrain Warning (TAWS) with Terrain Awareness (color coding) in the cockpit.
Click to expand...
Where you are most vulnerable is when that stuff doesn't work.

It ALL depends on GPS. If that doesn't make you nervous, you don't understand the implications. One ***hole trucker is all it takes to ruin your whole day.

I've lost a GPS signal while on a missed approach in the clouds, out of possible contact with ATC due to terrain shadowing. Now if, in addition, the DG and compass started to lie because someone went ape**** adding unnecessary features, I'd be a smear on a hillside right now. As it was, I could hold runway heading and know the terrain wasn't there.

You change stuff when it doesn't work, or there is some benefit. Not because it makes shortsighted technology fans happier with the world to make it appear simpler than it is.

I'm quite happy that I was able to use a dirt-simple compass to get my ass away from some guy presumably trying to hide that he was at a surfing competition next to an airport when he should have been elsewhere.

I have terrain color coding available in the G1000 CAP aircraft. It has magically disappeared on occasion when one of the SD cards went TU. Not OK to bet my life on.
 
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