magnetic variation

Hmm, interesting question. I don't think I've seen it come up here before. I have always thought that in the flight sim (and in real life) all compass headings were expressed as local magnetic bearings, and the Heading Indicator was set to that. Yes, it changes over time, but it doesn't change fast enough to have to repaint the runway numbers every year. 😂

I haven't seen any way to compensate for magnetic declination in FS09, though.

If you don't get the answer here, it might be a good question to ask Microsoft. Or your flight instructor.

Perhaps some of the real pilots here will comment.

Ed

Funny you should say that Ed, but I have heard of a runway having to be re numbered in recent years 😕 ...can't remember which it was though 🙂

I've just started my navigation course and was surprised at the size and complexity of the magnetic variation even in the relatively benign UK (Canada must be really demanding). I've just bought my up to date chart of southern England (hardly the biggest place in the world 😀 ) and the variation (marked by isogonals) varies from 4.5 deg W in the West to around 2deg W oin the East coast. The rate of change is currently 7 min's a year (about a deg every 8 years then?)

Given that a 1 deg error over 60miles will put you a mile out you can see why we must work variation into our navigation exercises.

FS04 mentions how important variation is, but apparently doesn't allow you to enter it? 😕

Hi all;

You can rest easy knowing that the gurus at Redmond are awake. The
magnetic variation is already in FS9. It is not apparent though because the
heading indicator is slaved to the magnetic compass.

You will notice the effect if you plan longer flights using real world charts as
you will have to figure the difference between true heading(that the chart
is based on) and magnetic heading. Also you will probably not notice the
difference if flying IFR as all ATC directions, VOR Radials, Rwy numbers ect.
are given in magnetic.

Hope this puts your minds at ease 😂

DN

In the FS9 flight sim the heading indicator should agree with the magnetic compass. During long flights you need to "adjust" the heading indicator to the current compass heading. You can do that by pressing the letter "D" on the keyboard. I don't know if those two instruments get out of agreement due to "gyro drift" or to "magnetic variation". Either way just hit the letter "D" once in a while.

Yesterday, as I was flying my Missouri River tour a pop up box appeared that said "Your heading indicator is set incorrectly, press "D" to correct. So the flight sim warns you when the setting is too far off the compass heading. 😛

iannay wrote:

Funny you should say that Ed, but I have heard of a runway having to be re numbered in recent years 😕 ...can't remember which it was though 🙂

I've just started my navigation course and was surprised at the size and complexity of the magnetic variation even in the relatively benign UK (Canada must be really demanding). I've just bought my up to date chart of southern England (hardly the biggest place in the world 😀 ) and the variation (marked by isogonals) varies from 4.5 deg W in the West to around 2deg W oin the East coast. The rate of change is currently 7 min's a year (about a deg every 8 years then?)

Given that a 1 deg error over 60miles will put you a mile out you can see why we must work variation into our navigation exercises.

FS04 mentions how important variation is, but apparently doesn't allow you to enter it? 😕

Magnetic Variation varies quite greatly in the US. In Central US, the standard is around 5 degrees.

In aviation, Magnetic Variation should come into play only, as a previous poster inferred, when plotting a course on a VFR aeronautical chart then converting those course lines to magnetic directions or when answering FAA test questions.

VFR charts directions are shown in "true" directions while aircraft intruments and courses use magnetic direction. Thus, when you calculate a course direction from a chart, that course must be corrected for magnetic variation which occur as a result of the different locations of the earth's geographic and magnetic poles and magnetic forces flowing from the magnetic poles.

Every Sectional and Wide Area Chart shows the magnetic variation corrective factor to be applied for a particular area. These vary, even on the same chart. For instance (using an old chart), the Los Angeles Sectional shows MV at 13 degrees, 30 minutes East on a line running northeast across the north end of San Diego County and on into the desert, all the way to the magetic north pole. About 100 miles north, the MV is 14 degrees E, also on a line running northeast across the north end of Los Angeles to the pole.

Pilots must either subtract the MV for east variations or add the MV for west variations to true course in order to calculate magnetic course. (a memory jogger used to remember is "East is Least, West is Best). Thus, if the true course from one point to another is 100 degrees and the MV is 15 degrees East, the pilot must fly a course of 85 degrees magnetic, corrected for wind drift to reach the intended location.

MV can be as much as 20 degrees in the northwest and northeast US and is zero on a line running south-southeast from the Great Lakes to Florida.

As aviation tools modernize, this becomes less a factor since many aircraft are now equipped with VOR's and GPS's and many routes to be flown are already published with their magnetic courses. Pilots still have to know how to apply MV, however, in the cases where they have to plot a course on a VFR chart or, as stated earlier, to pass FAA tests.