Question about GPS mode

[ark 1,290]

1 hour ago, bpcw001 said:

OK. started now with the default P3D v4.4 F35.

 

All the same. 

Could you try the following, doesn't even require to make a flight.

 

Load the Lear35. Use the Hangar Panel and turn everything off using the "All systems off"  option.

Place yourself at threshold runway 25 at EDDS. Power up the Lear. Batteries, Inverters, and Avionics master. Let everything come up, especially the GTN 750. 

Have the GTN in VLOC mode.

Tune 116.85 into VOR2 (STG VOR). Observe correct indication in RMIs vor VOR2.

Now, in the GTN, put in 109.90 as active NAV1 frequency.

You should get vertical indicators on HSI1 since 109.90 is the ILS for EDDS RWY 25.

What are the RMI needles now showing for VOR2?

 

As far as I can see the pattern now, the problem on my system narrows down to the following: as soon as there is any kind of vertical guidance involved on the VOR1 channel, either from an ILS glideslope or from GTN's VNAV, I lose the VOR2 channel.

 

Thoughts?

Dave,

First, to do this test you need to put your a/c on runway 07.  Since the VOR is directly behind the threshold of runway 25 and on the runway center line, the RMI will point to the 6 o'clock position whether it is actually pointing to the VOR or is in its off position. 

I first tried the test with the Falcon 50 since I know the RMI code was updated to deal with localizers, etc, as mentioned above. RMI needle two pointed to the VOR (the 12 o'clock position since the a/c was on runway 07) both with and without freq 109.9 in Nav1, and in both the VLOC and GPS modes. So, all good.

As I mentioned above, I know the Lear has a bug in its RMI code as far as dealing with a localizer signal is concerned (and what other problems this bug could be causing I don't know). So I was not surprised the second RMI needle did not work correctly in this EDDS test under VLOC. It correctly pointed to the 12 o'clock position when there was no localizer signal tuned in on Nav 1, but went to the off position when there was a localizer signal tuned in on Nav1. So I think the bug is that BOTH RMI needles are getting 'turned off' when a localizer signal is tuned into Nav1 instead of just the first RMI needle getting turned off. Again, what other issues this bug could be causing I don't know, so I suggest you just ignore all RMI problems until FSW puts out the next Lear update.

Al

[bpcw001 22]

Hi Al,

OK, then. So there is an issue with localizers in the Lear 35, and VOR2 not indicating correctly in this scenario is expected. 

So we have at least clarified that this is not a peculiarity of my system. So far so good.

I suppose the GPS LNAV/VNAV guidance will also internally be handled on the LOC/GS channels, and hence the same behavior concerning VOR2 shows in that case.

Good to hear that this does not occur in the Falcon. However, I would of course be interested if (and when) the fixed RMI code from the Falcon will make it to the Lear someday.

So, I think we're finally through with this one.

I'd like to thank you Al for your patience and for bearing with me through all this. Great forum!

 

BTW: I put the aircraft at the holding point of RWY25 in EDDS which is perpedicular to the runway, so the STG VOR would indicate at 9 o'clock on the RMI. Putting the aircraft straight on RWY25 would have been, as you correctly suggested, pointless since STG would indicate 6 o'clock in both RMI operational and INOP cases.

 

Edited February 11, 2019 by bpcw001

[ark 1,290]

6 hours ago, bpcw001 said:

Hi Al,

OK, then. So there is an issue with localizers in the Lear 35, and VOR2 not indicating correctly in this scenario is expected. 

So we have at least clarified that this is not a peculiarity of my system. So far so good.

Good to hear that this does not occur in the Falcon. However, I would of course be interested if (and when) the fixed RMI code from the Falcon will make it to the Lear someday.

 

 

Dave,

The code for the Lear's RMI is in the interior model file, which is a complied file so I can't see it with a text editor to see what is going on. However, I did talk with FSW and we both think there is a typo of some type in that code. FSW confirmed the intent is to update the Lear's RMI code with the same type of code as in the Falcon 50 once the update for the Falcon 50 is done in a few weeks. Hopefully the RMI errors you are having that I could not reproduce will go away with the updated code.

Al

 

[bpcw001 22]

1 hour ago, ark said:

Dave,

The code for the Lear's RMI is in the interior model file, which is a complied file so I can't see it with a text editor to see what is going on. However, I did talk with FSW and we both think there is a typo of some type in that code. FSW confirmed the intent is to update the Lear's RMI code with the same type of code as in the Falcon 50 once the update for the Falcon 50 is done in a few weeks. Hopefully the RMI errors you are having that I could not reproduce will go away with the updated code.

Al

 

Cool. Thanks!

Fortunately, RMI issue is minor and definitely does not spoil my enjoyment of the Lear.

Outstanding support and communication with your customers!