A320 NAV PFD OBS Question

How come when the OBS is set course 007, PFD displays 006?

This is because 007 IMDE is a track (the actual direction the aircraft has to fly over the ground), whereas 006 refers to the heading the aircraft is flying (the direction the airplane is pointed).

The difference between track and heading is that track accounts for any winds you may have, whereas heading does not. For instance, suppose you were flying at a 007 heading towards IMDE with a strong crosswind from the right. As such, despite you flying a heading of 007, your aircraft will drift to the left and thus never actually pass over IMDE ILS/DME.

In the photo, you are flying the 007 track to IMDE ILS/DME. As such, your heading may differ due to the airplane attempting to correct for any winds, which is why we see 006 heading for a 007 track.

Hope this helps :)

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Wouldn’t that be the green indication though? With a track of 176. Thanks.

Credit: airbusdriver website

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Yes, that’s correct; and I believe there is a slight difference between the green diamond and the yellow heading indicator in your photo - but it’s hard to tell due to the 1-degree difference.

Normally you wouldn’t fly on HDG when attempting to follow a track (unless in NAV mode in the real aircraft) anyway. You’d use the TRK/FPA mode, which allows you to follow a track (such as a VOR radial) which also brings up something known as ‘the bird’ (flight path vector) on the PFD, which you can see only in the HUD view in Infinite Flight, for now.

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@Maxim I think it’s just a small error in IF. He’s just saying sometimes there is a 1 degree discrepancy between the OBS select value (007) and the magenta value in the PFD (006) when in theory these values should be the same. I’m no Airbus expert though so…

Let me know your thoughts?

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Oh, I see! I’ve completely misunderstood the question, thanks for pointing that out, @Cody_M!

Indeed, the magenta box should depict the preset course towards the ILS/DME in this case, which yes, should be 007 instead of 006. I’ll play around with it and report it to the developers if this turns out to be a consistent issue.

I for some reason interpreted the question as to why is the heading different when flying on a certain degree track…

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No worries just wanted to clarify :) Good to hear from ya @Maxim

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