LOC WILL BE TUNED Message in FMC overriding MAN radio setting

[ual763 81]

So flying the ILS RWY28R approach into SFO today I had input the ILS Freq into the NAV1 radio on the arrival via manual.  I then also input a VOR used for the Missed Approach procedure into the NAV2 radio via manual.  On approach, I got an FMC Message saying that LOC WILL BE TUNED.  Sure enough, I looked down at the radios and my NAV2 had been switched to the ILS Frequency as well.  Should it autotune the ILS in Nav2 if the radios are both set to MAN?  Is that normal, or a bug?

 

Cheers,

Rob

[Nicco54 24]

LOC WILL BE TUNED appears when your radios are in MAN. Basically the FMS will perform the NAV to NAV transfer and this message will appear 30 seconds before the FMS tunes the LOC frequency.

If on the other hand you get the CHECK LOC TUNING it’s because the FMS cannot tune the NAV radios and the NAV to NAV transfer will not work.

In order for the NAV to NAV transfer to work the aircraft has to be within the terminal area of the destination airport, a localizer based approach is entered into the active flight plan, and you have white needles (FMS) selected as the source on both the Captain’s and the First Officer’s side.

I don’t know if the whole system is modeled in the Aerosoft CRJ but that’s how it works in the real aircraft.

Hope this helps

[ual763 81]

1 hour ago, Nicco54 said:

LOC WILL BE TUNED appears when your radios are in MAN. Basically the FMS will perform the NAV to NAV transfer and this message will appear 30 seconds before the FMS tunes the LOC frequency.

If on the other hand you get the CHECK LOC TUNING it’s because the FMS cannot tune the NAV radios and the NAV to NAV transfer will not work.

In order for the NAV to NAV transfer to work the aircraft has to be within the terminal area of the destination airport, a localizer based approach is entered into the active flight plan, and you have white needles (FMS) selected as the source on both the Captain’s and the First Officer’s side.

I don’t know if the whole system is modeled in the Aerosoft CRJ but that’s how it works in the real aircraft.

Hope this helps

Makes perfect sense.  Thank you.

[ual763 81]

1 hour ago, Nicco54 said:

LOC WILL BE TUNED appears when your radios are in MAN. Basically the FMS will perform the NAV to NAV transfer and this message will appear 30 seconds before the FMS tunes the LOC frequency.

If on the other hand you get the CHECK LOC TUNING it’s because the FMS cannot tune the NAV radios and the NAV to NAV transfer will not work.

In order for the NAV to NAV transfer to work the aircraft has to be within the terminal area of the destination airport, a localizer based approach is entered into the active flight plan, and you have white needles (FMS) selected as the source on both the Captain’s and the First Officer’s side.

I don’t know if the whole system is modeled in the Aerosoft CRJ but that’s how it works in the real aircraft.

Hope this helps

One more question since you seem to fly the real thing....  Is there a way to preselect a CRS while in the white FMS mode?  I’ve been switching momentarily to HDG mode, switching to green LOC mode, changing the CRS reading, then going back to white/FMS & NAV mode.

[Svaly 7]

CRS is automatically settled. You don't need to do it by yourself.

[Nicco54 24]

7 hours ago, ual763 said:

One more question since you seem to fly the real thing....  Is there a way to preselect a CRS while in the white FMS mode?  I’ve been switching momentarily to HDG mode, switching to green LOC mode, changing the CRS reading, then going back to white/FMS & NAV mode.

No need, the CRS selection is automatic as Svaly said.
And yes I'm lucky enough to fly the real thing, only the CRJ 1000 though... They're wonderful airliners, just a little nose heavy on approach, but apart from that they're perfect to me

[JuiceBox7535 19]

On 3/17/2021 at 7:28 PM, CRJFullOfBugsDontBuy said:

Doesn't seem to be, it will not automatically switch from white to green needles on capture as should happen with a nav-to-nav approach.

 

It will if you are setup correctly. The FMS will auto tune the ILS frequency, set the inbound course, and do a NAV-to-NAV transfer (from FMS nav source to LOC). Of course it must be setup correctly. You have to load the procedure from the FMS DEP/ARR page (with the legs sequenced properly), arm APR mode, and be within the capture parameters for it to transfer.

 

Will get a blue LOC needle in the background, and then it will change from FMS1 in white to LOC1 in green, all automatically. No need to manually change the nav source on an ILS (I know some operators do it manually per SOP if they fly a mix of older aircraft, etc). 

 

This is what it looks like just before and just after auto transfer, the last time I flew it. If you are seeing something different, please provide details so we can troubleshoot (and a screenshot if possible).

 

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