ILS Flight Director Influenced by Course Selector

[Joni]

Rwy 31 of Vaziani has the same frequency because it actually has just one ILS antenna for rwy 13. It can be used for rwy 31 but through a Back Course approach. DCS does not model Back Course approaches and therefore using the same frequency for rwy 31 gives us off track indications.

[Snoopy]

The 476 has done an outstanding job of doing unofficial plates that aren't available for most users otherwise.

 

I will say that there appears to be something broken with the approaches at Vaziani.

 

PM sent explaining the likely reason for this behavior.

[Joni]

PM sent explaining the likely reason for this behavior.

 

"Rwy 31 of Vaziani has the same frequency because it actually has just one ILS antenna for rwy 13. It can be used for rwy 31 but through a Back Course approach. DCS does not model Back Course approaches and therefore using the same frequency for rwy 31 gives us off track indications."

 

 

 

Snoopy, can you share that please? I already stated the reason, but it'll be good if you share your opinion so we can all check.

[Snoopy]

Snoopy, can you share that please? I already stated the reason, but it'll be good if you share your opinion so we can all check.

 

The default runway in DCS World at Vaziani is runway 14, even if the runway changes to 32 if the winds are not more than 5 mps the ILS doesn't switch ends. My guess is in the images above the active changed but the winds were not high enough for the ILS to change.

 

Found this out when we developed our 476th charts.

[Joni]

I didnt know that ILS needed to change... Is that due to the back course?

[Snoopy]

I didnt know that ILS needed to change... Is that due to the back course?

 

It's simply how ED modeled it in the sim.

[PFunk1606688187]

As per usual we're beating each other up over a peculiarity of the sim.

 

Détente pl0x.

[Havner]

Assuming I understand the OP properly I noticed a strange thing. I can reproduce the OP behaviour of yellow needle being dependent on HSI heading as well and I found that strange. But this only happens up to more or less short final (no beacon on batumi where I tested).

When you're close to the airport the needle stops being dependent on the heading. So this is even more awkward.

 

Find the track attached where I show this. At the short final when I rotate the heading knob the needle stops reacting to this.

 

Don't laugh at me for the hard landing. I started to learn A10C a week ago...

 

EDIT: I have not read the whole manual yet, so my only reference as to what happens at this point is this thread.

A10C-ADI.trk

Edited August 13, 2015 by Havner

[Justin Case]

One of the things I encountered that does not work like in real life is the Flight Director during ILS approaches. In real life flight directors are not influenced by the HSI course selector since an ILS trasnmitter only emits one signal in an unique direction and therefore both the HSI and flight director track that one alone.

 

The HSI works fine, it is not influenced by the course selector, but the Flight Director is and makes landings in IMC very difficult for some airports.

 

Hi! Take a look at this old thread from pprune. http://www.pprune.org/archive/index.php/t-279352.html

 

Of course this might only be true for the Boeing 737 but it could be an indication for similarities in other ILS and FD systems. It's kind of like flying a raw data ILS with the HSI course incorrectly set 20 degrees off, it's possible but the initial intercept will probably be messed up even though the needle in the HSI shows a correct indication.

[majapahit]

I just recently reentered DCS and come from a long time of studying and practice of navigation (naval), some private flights and many years of FSX.

 

Piston85 OP's observation

'- In real life flight directors are not influenced by the HSI course selector'

seems to be correct, as far as my experience with RL and is modeled in FSX, and which peculiarity I also noticed in DCS.

 

As an addendum I can also confirm Havner comment (Batumi)

'- I can reproduce the OP behaviour of yellow needle being dependent on HSI heading as well and I found that strange.

- But this only happens up to more or less short final.

- When you're close to the airport the needle stops being dependent on the heading.'

 

This is even more awkward.

 

I have notices - I know for sure for Batumi - that a variety of ILS approach headings are mentioned in DCS docs, on the web, and when Virtual Squadrons start posting their own ILS heading data and sometimes mixed with RL (?) ILS data and for RWY 13 I have seen a variety from 110, 119 to 120 etc.

 

This could be compared probably/maybe with Jeppesen charts, if it were not that my Jeppesen is outdated (thus obsolete) :(

 

There's also the additional Piston85 remark about

'- check the course, then you need to subtract 6 degrees to account for the magnetic drift that DCS models.'

 

'subtract 6 degrees to account for the magnetic drift that DCS models' ?

 

With my - admittedly limited - flight background I can extract

 

- DCS ILS headings are not correct in the charts (I now this because I noticed)

- ILS heading data for the DCS area can be found published in a wide variety of numbers, with even RL numbers more than often probably outdated or plain incorrect

- up-to-date ILS headings should INCLUDE magnetic drift (as far as I know (?))

- HSI should NOT influence ILS FD

- an HSI 'influencing of ILS FD' that stops influencing the ILS FD when past or nearly over the final marker is indeed peculiarly weird

 

- it appears DCS ILS heading data are or could even purposely be based on obsolete and outdated data, following a choice for a RL trend, i.c. I can vaguely remember that even Jeppesen might not have updated data for this area

- RL these data seem or might not be publicly published, and are only disclosed to aircraft with permission to land these airports (the same situation as in war zones)

- DCS might have information of the real data (not too hard to obtain, simply call a few pilots), but doesn't want to publish, for this would hurt their relationship with the authorities in this region (?).

 

Conclusion would should or could be

- HSI influencing ILS FD when approaching final marker likely is a bug

- 'until ILS signal close enough for ILS to operate on its own' (?) somewhere over the Final Marker I noticed, so at decision height your ILS works :)

- DCS should publish the proper sims magnetic ILS headings (they hardcode these for heaven's sake), and without the 'subtract 6 degrees to account for the magnetic drift that DCS models'

- because who needs that

- or, publish both magnetic and GPS headings and update these with a 'shelf life' as frequent as is common in RL (i.e. the aviation authorities and Jeppesen)

 

2 cts

Edited August 19, 2015 by majapahit

[Joni]

Hi folks, I worked with Lino to integrate the magnetic courses for each ILS in DCS so we can make real approaches with all systems working as they should.

 

Please check the thread below to download the file.

 

http://forums.eagle.ru/showthread.php?p=2450713#post2450713

 

 

This is only necessary due to this bug (or missinterpretation from ED on how the systems work), but will indeed help us mitigate its impact on our simulation.

 

Hope it helps you.

[majapahit]

EDIT:

and DCS should extend their published 'aerodrome charts' and VFR approach charts to include all necessary proper approach charts, i.c. (aside VFR) NDB DME and in particular ILS, and IFR per airplane category and capabilities and differentiated per Runway and its capabilities and accompanied with all discretionary NOTAM's as per how all the official aviation authorities do this,

 

and this data will shift periodically per airport changes and per magnetic drift

[Snoopy]

EDIT:

and DCS should extend their published 'aerodrome charts' and VFR approach charts to include all necessary proper approach charts, i.c. (aside VFR) NDB DME and in particular ILS, and IFR per airplane category and capabilities and differentiated per Runway and its capabilities and accompanied with all discretionary NOTAM's as per how all the official aviation authorities do this,

 

and this data will shift periodically per airport changes and per magnetic drift

 

Take a look at the 476th charts, we've done that on a limited basis for the main airfields we use.

 

http://www.476vfightergroup.com/downloads.php?do=file&id=218

 

I'm going to bump what Piston85 posted against the our charts to see if we have major differences. How I established runway headings was place a jet on the end of each runway, tune TACAN and dial the HSI until everything lined up.

Edited August 19, 2015 by Snoopy

[majapahit]

Hi folks, I worked with Lino to integrate the magnetic courses for each ILS in DCS so we can make real approaches with all systems working as they should.

 

Please check the thread below to download the file.

 

http://forums.eagle.ru/showthread.php?p=2450713#post2450713

 

This is only necessary due to this bug (or missinterpretation from ED on how the systems work), but will indeed help us mitigate its impact on our simulation.

 

 

the updated version's link is

https://www.digitalcombatsimulator.com/en/files/585582/

to the DCS Users Files repository

 

THX, I'll try and dial in the proper ILS heading at Batumi now, and than find out if I can actually fly in IFR in zero viz. (I saw a Youtube where somebody show off his proficiency in this, but - given there's a bug in th system - that only works if you know the exact heading if the ILS (somewhere '130' for RWY 13 aint good enough by a long shot)

 

 

 

EDIT:

actually,

I just wanted to check above data in DCS and entered Mission Editor, and waddojonow,

 

if I zoom in to the ILS there are actual ILS headings stated (very fresh latest openbeta 1.2.16.xxxx).

Batumi RWY13 says 126dgs, where 126 would be True Heading,

 

thus Piston85's 'minus 6 for magnetic' is implemented which is awkward,

 

at least in Western Aviation on a chart that would and should state the Magnetic numbers.

 

Stating True Bearings would be easier for DSC (its always correct) but a. should be mentioned or stated throughout that this is the case (its really important to know), b. perhaps I'm getting too old, but RL 'dead reckoning' navigation as per VFR and ILS is still done with the magnetic data (right?)

 

oh,

476 vFG Flight Info Pubs,

concerning Batumi RWY 13 mentions 120dgs, which is Magnetic Heading, and the proper way to publish

(you DCS, you, yes I'm talking to you)

 

:)

Edited August 19, 2015 by majapahit

[Joni]

this isnt the case for DCS. there is no unification in units or data. the mission editor's headings are geographic, so you will need to take the 6° off them.

[majapahit]

this isnt the case for DCS. there is no unification in units or data. the mission editor's headings are geographic, so you will need to take the 6° off them.

 

thats a good and valid point to make, concerning the mission editor, but as a pilot, I am deeply offended it not being a 'chart'.

 

:)

 

(DCS should state for clarification whatever units they implement where - and in the manual explain why)

[Joni]

DCS could do a lot of things better, but the truth is that building these kind of simulations is quite hard, and given that the revenue is very poor I think we should be greatful of having DCS.

 

I do agree that it makes one get frustrated but that's life.

 

I put that file together so that we can have a good experience despite these navigational bugs.

 

 

And as a pilot I suffer these things a lot, but ED is working hard to bring us DCS 2 and that will be the start of a new era that will make all of us enjoy this even more.

 

 

Sorry for the long post, I got melancholic.

[majapahit]

Sorry for the long post, I got melancholic.

 

That what the pampas of Argentina do to your heart I suppose :)

 

Any way

 

tried the ILS heading on

Kutaisi-Kopitnari (UGKO) Runway 08 068°/074° ILS 109.75 MHz

 

oopsie No ILS reception (?)

the reason its missing in the 476 vFG file?

 

tried

Batumi (UGSB) Runway 13 120°/126° ILS 110.30 MHz

 

that works

 

Also found out what that seemingly redundant Yaw (Rudder) Trim on the SAS is for,

when you dial in 16ktn crosswind and plenty of turbulence on your ILS approach,

 

that Yaw Trim all of a sudden has great function :pilotfly:

[Snoopy]

 

tried the ILS heading on

Kutaisi-Kopitnari (UGKO) Runway 08 068°/074° ILS 109.75 MHz

 

oopsie No ILS reception (?)

the reason its missing in the 476 vFG file?

 

We don't use Kutaisi often so we didn't create any departure or approach plates for it.

 

I'm going to bump what Piston85 posted against the our charts to see if we have major differences. How I established runway headings was place a jet on the end of each runway, tune TACAN and dial the HSI until everything lined up.

 

Besides us having a decimal included in the runway heading (similar to real world FLIPs) our runway headings are the same as what Piston85 posted. So our charts are good as published.

Edited August 19, 2015 by Snoopy

[majapahit]

Besides us having a decimal included in the runway heading (similar to real world FLIPs) ..

 

Having a decimal in (many of your) runway heading is quite a nice touch. I think, but.

 

'similar to real world FLIPs', though, I have/had never seen decimals in Runway headings before.

 

Jeppesen doesnt as far as I remember, if i google 'Jeppesen' @images in the multitude of jeppesen charts, there is no decimal.

 

Your team member here mentioned numbers 'were extracted' direct from DCS.

 

So it appears DCS enters True Headings with a decimal in the DCS F10 'Real World MAP' (per Piston85's remark) which I personally still is horrendous really (my voice trembling here),

 

should be a all-overview-electronic Chart :) thus with magnetic headings as per navigational tradition, or, you add a compass chart somewhere at the bottom, with directions on what is what (magnetic deviation, indication of true headings & method of map projections useful for longhaul cross ocean route planning (wth?)), as per RL navigation (naval) charts.

 

Publishing the decimal is not what Air Authorities seem to do.

 

?

[Snoopy]

Publishing the decimal is not what Air Authorities seem to do.

 

You may want to do some research because the FAA does.

 

http://aeronav.faa.gov/content/aeronav/online/pdf_files/legendAD.pdf

 

 

 

 

[majapahit]

thats new, or rather is FAA, for just checked Schiphol here EHAM (official AIP charts), and without decimal

http://www.ais-netherlands.nl/aim/2015-07-09-AIRAC/eAIP/html/index-en-GB.html

Edited August 20, 2015 by majapahit

[Snoopy]

thats new

 

No it isn't.

[majapahit]

No it isn't.

seems redundant though

here, we dont have a need for that (who does):)

[Snoopy]

seems redundant though

here, we dont have a need for that (who does):)

 

You said our charts were wrong, I showed you that they are in fact correct based on the FAA's format. If you don't feel you need them then don't use them, we wanted to develop charts that mirrored FAA charts.

Edited August 20, 2015 by Snoopy