# I don't understand why my magnetic and true heading is totally different

My magnetic heading is 332 degrees and my true heading is 22 degrees. I’m at 35,000 ft. I’m tracking my flight on LiveFlight. It’s heading north and it’s in the 360 degrees to 179 degrees region as pointed out in this chart:

What I don’t understand now is that should I just follow my magnetic heading of 332 degrees and change to FL 340 or 360 instead because 332 degrees is in the 359 degrees to 180 degrees region. Am I at the correct cruising altitude?

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I don’t understand what’s being asked here…

I believe the cruising altitude rule uses true heading…

So you have a few different things going on here.

You will follow your magnetic heading, as that is what a compass/PFD will show you. This will differ from true heading and if i remember correctly, the further north/south you are and close to the poles, the more of a difference you will encounter.

While your heading may be one thing, your actual course may be a few degrees off from that. This is due to the wind direction and velocity.

So, your plane may be pointed at 360 due to the wind and velocity, but your actual course over the ground is 022 degrees.

The direction in which your plane is traveling, is what you will set your altitude too, not necessarily the direction it is pointed in this case.

NEODD North-East ODD
SWEVEN South-West EVEN

a real pro like @DeerCrusher could be of more help

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True heading measures your heading relative to geographic North — if you look at the lines on the IF globe, they all come together at the poles. These are the points that the earth rotates around. That’s geographic North.

Magnetic heading measures your heading relative to magnetic North — where a compass would point, it’s somewhere like northern Greenland, and shifts (slowly).

If you’re flying in the extreme north or south, these numbers can be quite different. You should follow the magnetic course* you are flying, and choose your altitude based on that.

*course is the path you are flying. You might be pointed to a magnetic heading of 358, but because of a strong west (from your left) crosswind you might be flying a course of 003. That’s the number you follow.

TL;DR: Follow magnetic course and descend/climb 1000 feet.

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So from your example, I should follow the magnetic heading of 358 and decide on an even cruise altitude, even if the aircraft seems to be flying north-east?

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No, cruise altitude is always based on magnetic course. So in that case it would be odd, based on 003.

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Lol it’s so confusing how about another example if it’s a magnetic heading of 332 degrees and a true heading of 22 degrees, should it be odd or even?

In my humble opinion, for the purposes of IF, disregard true bearing because thats the bearing you get BEFORE magnetic variations are calculated. Everything in IF is ALREADY calculated. I guess in the days prior to all this tech that thinks for you, pilots of old had to do the calculations manually based on where there were in relation to the magnetic poles.
I believe what I’m saying is accurate, if not, feel free to correct me.

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If I’m understanding what you’re asking, you might be seeing something called Magnetic Declination. True North and Magnetic North differ due to the magnetic field differences from the actual north pole.

The north pole that you’d normally associate is not actually in the northern hemisphere. If you recall from a physical science class, you may remember that a north and south pole of a magnet are attracted. When we are in the plane, we’re using the north pole of the magnet. And the earth is the south pole in this example when in the northern hemisphere. The opposite is true when you’re in the southern hemisphere.

With that said, a deviation/decliniation exist as we move about in various parts of the planet as a result of interference that may exist in out atmosphere. For that reason, we need to add or subtract a number of degrees from our heading to get our magnetic heading. The map below shows the various magnetic declination values. If you’re flying a heading, and you’re within the red area you’ll add the value of degrees to your heading to get to your magnetic heading. If you’re in the blue area, you’ll subtract the value of degrees to get your magnetic heading. If I recall correctly. 🙂

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I think I kind of get it now. With a perfect condition of 0 kt wind my magnetic and true heading would probably be the same but due to a strong crosswind from the left it isn’t. So I guess for my case I should be flying at even cruise altitudes.

Alright thanks for your help guys you’ve answered part of my question but just a clarification on whether I’m doing the right thing.

Should I be at FL 360 (even) or FL 350 (odd)? Given that my mag heading is 348 and T heading is 14.

You should be flying odd thousands look at your crosswind.

Ok so if there’s no wind (0 kts) complete calmness it should be even thousands?

According to 91.179, you should be flying EVEN thousands. Your magnetic course is 348. Although the crosswind is requiring you to point the nose 014 degrees, you are traveling 348 degrees. FL360 is an appropriate altitude

## IFR cruising altitude or flight level.

Unless otherwise authorized by ATC, the following rules apply—

(a) In controlled airspace. Each person operating an aircraft under IFR in level cruising flight in controlled airspace shall maintain the altitude or flight level assigned that aircraft by ATC. However, if the ATC clearance assigns “VFR conditions on-top,” that person shall maintain an altitude or flight level as prescribed by §91.159.

(b) In uncontrolled airspace. Except while in a holding pattern of 2 minutes or less or while turning, each person operating an aircraft under IFR in level cruising flight in uncontrolled airspace shall maintain an appropriate altitude as follows:

(1) When operating below 18,000 feet MSL and—

(i) On a magnetic course of zero degrees through 179 degrees, any odd thousand foot MSL altitude (such as 3,000, 5,000, or 7,000); or

(ii) On a magnetic course of 180 degrees through 359 degrees, any even thousand foot MSL altitude (such as 2,000, 4,000, or 6,000).

(2) When operating at or above 18,000 feet MSL but below flight level 290, and—

(i) On a magnetic course of zero degrees through 179 degrees, any odd flight level (such as 190, 210, or 230); or

(ii) On a magnetic course of 180 degrees through 359 degrees, any even flight level (such as 180, 200, or 220).

(3) When operating at flight level 290 and above in non-RVSM airspace, and—

(i) On a magnetic course of zero degrees through 179 degrees, any flight level, at 4,000-foot intervals, beginning at and including flight level 290 (such as flight level 290, 330, or 370); or

(ii) On a magnetic course of 180 degrees through 359 degrees, any flight level, at 4,000-foot intervals, beginning at and including flight level 310 (such as flight level 310, 350, or 390).

(4) When operating at flight level 290 and above in airspace designated as Reduced Vertical Separation Minimum (RVSM) airspace and—

(i) On a magnetic course of zero degrees through 179 degrees, any odd flight level, at 2,000-foot intervals beginning at and including flight level 290 (such as flight level 290, 310, 330, 350, 370, 390, 410); or

(ii) On a magnetic course of 180 degrees through 359 degrees, any even flight level, at 2000-foot intervals beginning at and including flight level 300 (such as 300, 320, 340, 360, 380, 400).

[Doc. No. 18334, 54 FR 34294, Aug. 18, 1989, as amended by Amdt. 91-276, 68 FR 61321, Oct. 27, 2003; 68 FR 70133, Dec. 17, 2003; Amdt. 91-296, 72 FR 31679, June 7, 2007]

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That is incorrect information his heading is 348 not his course. If his course was the same as his heading the flight path indicator would be inline.

@anon91707592 you are still getting it wrong. @tomthetank explained it really well above. think of it like a globe you have in your home. its true north is north pole. and put a giant magnet inside it like the earths iron crust that gives it its magnetic field. for some reason disallign the magnet a bit inside globe. now the location the magnetic south pole is poonting is our magnetic north pole. but we know true north pole is exactly north pole. magnetic north shift west slowly over time. our true north remains the same i.e. north pole. we always follow magnetic heading. and since its always shifting you’ll find many airports re print the runway heading over time because it no more corresponds to magnetic heading. what was runway 18 may become runway 19 after 10 years. at present magnetic north is between greenland and canada.

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Actually he’s exactly right if you have 0 wind your magnetic course and heading will be exactly the same.

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no. look at this image. it shows the true north that is the north pole where earth rotates in its axis and magnetic north.

now think you are standing at point b in russia where your true north and magnetic north will show the same direction. untill you reach north pole where after passing it your true north is to ypur south and magnetic north is still ahead. now at point A your compass will show north in different direction where’as the true north pole is in other direction.

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