Don't get caught out by an ILS!!

[JonathanRichardson]

Hi

I thought this might be a useful general post re ILS as I bumped into this problem...

We have a function in the CDU for Autotune of the NAV radios (added for 747 originally) but as I have found out it needs to be used with consideration in FS and with the new navdata updates. The ILS signal itself is sent from FS, but the new navdata may have updated frequencies, as such it is possible for the CDU to set a ILS frequency that does not exist in FS automatically.

I have recently been flying (for the first time) into Dublin for various tests runway 28. And here there is one such miss-match. The problem is, you can override the correct (real world frequency) to the FS old frequency, and thus perfrom an approach with this old FS signal/frequency *but* the CDU will eventually look at the real world data again (its primary source) and re auto tune, overiding what it thinks is an error on the manual selection by the pilot to the correct real world frequency in knows from the navcycle update, so when this happens in CATIII at 500ft you suddenly find yourself with no ILS.

My suggestion is unless you are 100% sure frequencies match, switch off autotune navs. That is unless you change the FS sceneries themselves to match the real world ones. This might be a rare thing to happen - but it obviously can....

I think this might explain some peoples loss of autoland in the past. Also, make sure you set the runway heading always in the MCP heading window.

Regards
Jonathan Richardson
Project Magenta

[PDT 200]

The other solution is to use AFCAD or it's partner for FSX and change the ILS freq in FS! Then no more problem with Autotune freq drift.
Regards,
Brian

[michelmvd]

Hi Jonathan,
Thanks to share you experience here regarding the real life data / old FS data.
Indeed as Brian, I too always try to change first the Afcad file.

Maybe if Enrico have once some time left, it would be good to bring the function in line with the real one.
When you have autotune available as in B747-400, it is still so that when you manually put in an frequency, this one has priority and it STAYS tuned until you delete the freq.

Would be great if you could let it work that way, as well with a special line for the ILS (syntax XXX.XX/XXX (freq/heading) in the B744 version ;) ;)

Many thanks

Michel

[JonathanRichardson]

>When you have autotune available as in B747-400, it is still so that when you manually put in an frequency, this one has priority and it STAYS tuned until you delete the freq.

Hi Michel

Agreed - that indeed would be a very good idea. That one certainly can cause problems, and lead to customers reporting problems of unknown cause re their approaches.

Regards
Jonathan Richardson
Project Magenta

[mmakela]

how to turn autonav off? Where is the ini to modify? Thanks!

[PeterH]

Hi,

You can do that on the CDU.

Merry Christmas and Happy New Year.

Peter

[michelmvd]

>
Agreed - that indeed would be a very good idea. That one certainly can cause problems, and lead to customers reporting problems of unknown cause re their approaches.




Thanks Jonathan for your understanding and it would only make the CDU more in line with the real B744 ;)

Seasonal Greetings

Michel