Couple of instrument questions


  1. When I fly heading 90, in the GPS display in the HUD, I seem to fly slightly NE in Chicago and slightly SE in Sydney. Is this just my imagination, or does this have something to do with magnetic versus true North or something? If the latter, is that significant to IFR flying, or does everything (runway numbers, bearing indicator, A/P heading) conform to one or the other, so the distinction isn’t terribly significant?

  2. Trying to do ILS approaches in low visibility. I have only been marginally successful. When I get the runway in sight, even though I seem centered on the localizer, I often seem a few degrees left or right of the runway. Is this just my lack of aviation skill, or are there some data inaccuracies in the game? Or do these inaccuracies exist in real life? Is there some additional adjustment I should be making besides being centered on the localizer?

Thanks for any advice.

For the second one, the runway heading won´t always be at the heading shown by the autopilot. The best solution is to fly down while making slight corrections to the heading manually.

1 it’s because of the curvature of the earth.
2 I don’t know but I does happen to me.

This happened to me in the London region, Coming into London Gatwick with very low visibility, I thought I was correct but when I was 1nm out I saw the runway lights and had to quickly change course.

I think it’s a bug, so we just have to wait and see really.

Tricky one. I’m not entirely sure about this but as we all know the runway numbers represent their magnetic heading. The magnetic north pole is not on the pole nor stationary. Currently it is somewhere over Nort Canada. Now you are flying a HDG 090 (mag) but your TRUE HDG is 070. So you are flying in a direction of 90 degrees in relation to the magnetic north pole. Sao Paolo’s (GRU) parallel runways are interesting. Indicated as RWY 09L/R but the true runway bearing is around 070. So I’m guessing this is all about the relation between the two poles.

If you have a crosswind or even slight wind, your airplane’s heading (the direction your nose is pointing) won’t be the same as your track (the direction in which your plane moves). This is perfectly normal in IF. Focus on LOC not your HDG.

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I always get in the center line of the runway when using the ILS in low visibility. The localiser becomes very sensible the closer you get to the runway and that’s why it can seem like when you are at long final you seem established but you are a few meters off, you will just have to make minimal adjustments along the way.


Thanks. Rather than litter the forum with a bunch of dumb questions, I’m going to add another instrument one here. This is about glide slope. The below seems to be saying to slow my rate of descent? but then it seems I would overshoot the runway? This is KRZL runway 18. Is there a point at which I should not watch glide slope? 210 feet is still above decision height? So I’m sure if I did not have a visual reference I would overshoot this.

Stabilize, intercept, follow. You can’t overshoot that way, even if it looks like you will.

Well as I said it becomes very sensible the closer you get to the runway, right now it’s just a matter of meters that you are below, so no need to worry too much about it.

I had about 9km visibility once with my 77W. When I saw the runway FINALLY, I had to go around for another approach.

Magnetic declination is the reason why your magnetic heading results in different true heading depending on location.

Put in your bar Distance to Destination. You will have a better idea about your location.

Yeah i was prepared at very low speed, about 140kts when I saw the runway