reported ADF Bearing Inaccurate in North Up

[Chain_1]

The ADF bearing circle on the HSI works fine in Track Up, but it doesn't follow the magnetic bearing when you switch to North Up.  Instead it maintains the same position on the outside of the compass rose.  I.e., if it is at the 12 o'clock position in Track Up flying west, it remains at the 12 o'clock position in North Up instead of moving to the 9 o'clock position to maintain the correct magnetic bearing.  Track attached.

adftest.trk

[randomTOTEN]

The RL manual (that I can see) doesn't mention anything about "magnetic bearing." It only uses the term "ADF bearing," which I would traditionally assume is a relative bearing (as that's how civilian equipment works). But it's possible the system could be running some sort of conversion. If what we're seeing is a raw direction find of the signal, then the behavior in your track is correct.

Edited April 3, 2022 by randomTOTEN

[Chain_1]

Even then, the bearing would be inaccurate.  Using the example above, after switching to North Up the bearing would indicate that the NDB/VOR was off the aircraft's right wing, when it would actually be off the aircraft's nose still.  I understand a few degrees difference for true vs magnetic (and I probably should've phrased my first post that way), but not moving at all around the compass rose just gives bad info to the pilot.  To be fair, though, I haven't shot an NDB approach in over ten years, so you may be right.  We'll see what the team comes up with.

[BIGNEWY]

Im not 100% on this but I have reported to the team to have checked

thanks