FMS VOR bearing and V/L radial tracking issues

[PMSoares]

I'm experiencing two issues regarding conventional navigation in the A-300. 

 

First is a disagree between the bearing to a VOR in the FMS PROG page, as can be seen in the picture below. The course to the VOR is 228, as shown in both the HSI and the RMI. However, according to the FMS the  bearing to the same VOR is 224. It seems the FMS is not taking in consideration the station´s magnetic variation, which ios precisely 14 degrees west. 

 

 

Another issue i'm experiencing is when tracking a radial to/from a VOR using the V/L function. The plane is not tracking ir properly. It seems that the same issue with magnetic variation is affecting the VOR/LOC autopilot tracking. Even without any wind, the plane drifts to the right of the radial when V/L is selected and the FMA goes from VOR to VOR *, which means the AP/FD is trying to capture the radial. 

 

 

 

 

 

After a while, the plane eventually flies paralell to the intended course at half dot deflection as cn be seen in the picture below:

 

[Deleted Account]

Thanks for the report, will look into and fix it 🙂

[Rene Feijen]

Is the autopilot  able to track a VOR course radial?

[ual763]

I also noticed when tracking a VOR radial inbound in V/L lateral mode, upon entering the ‘cone-of-confusion’ when nearing the VOR, as the course needle starts to quickly move outwards, the plane attempts to follow it and subsequently turns quite a ways off course.

[MarcusVT]

I can´t even tune VOR, it's off. 

[Deleted Account]

Need to flip the switch on the FCU

[falcon71]

I can confirm, that the VOR mode does not change from capture to tracking mode. This screenshot was taken from the OIII OBRI2A departure. I captured the VOR in manual flight before turning the AP on. It tracked the VOR somewhat, bit did not switch to tracking mode.

[Deleted Account]

Thanks, can confirm that the mode isn't changing, but tracking worked fine for me.

[MarcusVT]

And I don´t know if I'm doing anything wrong, but vor direction pointer to VOR at HSI isn't working either. Like it seems to be shown in first image above with both indicators are horitontal.

Edited March 29 by MarcusVT

[richboy2307]

Hi please try again in the latest update (v1.1.0) and let us know if this is still an issue.

Thanks!

[unhinged_aviator]

Speaking of which, where the heck is the DME information displayed when tracking a VOR?

Tried a VOR approach last night and couldn't find it.

[richboy2307]

DME readout is on the gauge left of the ND.

[UpUpandAway]

Unfortunately the RMI seems to be affected by variation, CTV at FACT in this example. I'm pointing straight at the station, but the needles are (about 26 degrees) off:

I can further confirm this after parking on stand. The VOR is behind me, to the left:

But the RMI shows it's to my right:

When I enter the VOR on the PROG page, the bearing to the station is shown true, without the 26 degrees magnetic variation.

[UpUpandAway]

Should I report this variation anomaly elsewhere, or is it an acknowledged bug?

[Crabby]

On 4/14/2024 at 5:56 AM, UpUpandAway said:

Unfortunately the RMI seems to be affected by variation, CTV at FACT in this example. I'm pointing straight at the station, but the needles are (about 26 degrees) off:

I can further confirm this after parking on stand. The VOR is behind me, to the left:

But the RMI shows it's to my right:

When I enter the VOR on the PROG page, the bearing to the station is shown true, without the 26 degrees magnetic variation.

I am not sure that comparing the guages to the placement of a scenery object is correct.  Is that airport default?  To my knowledge, the guages read the navdata files (sim or Navigraph depending on ability.) If you want to make sure that you are not having a magdec issue, use the file available here. Flight Simulator Aircraft Dynamics and NavData (sors.fr)

[UpUpandAway]

I've already used Hervé's file, no change unfortunately. Default airport.

In my first screenshot, I'm 17.5 nautical miles from the station flying directly towards the airport (visually and according to FMC). Using basic trigonometry, that 26° offset on the RMI would put the station 8.5 NM away from the airport!

I'm suspecting it is related to the aircraft dealing with variation or station declination, as I've experienced other variation related issues affecting the FMS:

The above issue was fixed for 1.1.1, the VOR bearing/declination issue remains.

Edited May 1 by UpUpandAway

[UpUpandAway]

To further illustrate the point, see comparison below, all aircraft roughly pointing at the VOR (CTV 115.70):

Fenix A320                                                                                  iniBuilds A310

iniBuilds A300:

The A300 RMI is off by what appears to be the airport's magnetic variation (26°W), despite the CDI on the ND actually being centered on a valid radial.

Edited May 1 by UpUpandAway
Format

[richboy2307]

On 5/1/2024 at 4:30 PM, UpUpandAway said:

The A300 RMI is off by what appears to be the airport's magnetic variation (26°W), despite the CDI on the ND actually being centered on a valid radial.

Thanks for this, noted and reported!

I loaded up at FACT to check. And can confirm the RMI is reading the TRU bearing instead of MAG bearing. Need to adjust the data source for the RMI.