How to use the O/M/I marker lights.

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Styggron
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How to use the O/M/I marker lights.

Post by Styggron »

Hello everyone,
I seem to be a littler perplexed here. I've searched, looked around but not found anything that really helps so I thought I would ask the good community here.

I have some questions about OMI marker lights and them lighting up in the cockpit.

Questions:
1. If an airport has ILS facilities, do the OMI markers lights automatically light up themselves if you are tuned into the ILS frequency on NAV 1 ?
2. Are the OMI lights only available on airports with ILS ? and if they are available at airports without ILS, how do you use them ?
3. Can I set the morse code to beep when the O is reached and again when the M is reached and again when the I is reached ? ie separately ? or are they all on the same frequency ?

Thanks everyone.
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Great Ozzie
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Re: How to use the O/M/I marker lights.

Post by Great Ozzie »

You can find info about the Marker Beacon system in the FAA's Aeronautical Information Manual (AIM) in paragraph 1-1-9(f) - link here: http://www.faa.gov/air_traffic/publications/. Also, check in the back of it in the Pilot/Controller Glossary for info on the Inner/Middle/Outer Marker.

Marker Beacons are part of the ILS system (described in the AIM) but are not tied to the ILS frequency. You don't need to set anything normally - unless needing to turn on the audio MKR button if there is one on the audio panel (e.g. the KMA 26). As long as as the sound is on, you will see and hear the appropriate light / sound when passing over each marker.
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Styggron
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Re: How to use the O/M/I marker lights.

Post by Styggron »

Great Ozzie wrote:You can find info about the Marker Beacon system in the FAA's Aeronautical Information Manual (AIM) in paragraph 1-1-9(f) - link here: http://www.faa.gov/air_traffic/publications/. Also, check in the back of it in the Pilot/Controller Glossary for info on the Inner/Middle/Outer Marker.

Marker Beacons are part of the ILS system (described in the AIM) but are not tied to the ILS frequency. You don't need to set anything normally - unless needing to turn on the audio MKR button if there is one on the audio panel (e.g. the KMA 26). As long as as the sound is on, you will see and hear the appropriate light / sound when passing over each marker.
Hello Great Ozzie,
THank you for that but I really need something more specific and direct to FSX. That link for the 726 page manual is interesting still though.

If they are not tied to ILS then they should just light up automatically in say the default C172 yes ? Thing is, it doesn't look like it does hence my question.

Also the A2A B377 Stratocruiser also has lights but they never seem to light up when approaching an airport with ILS

With the sound off surely I should still see the light ? They never seem to light up on airports with ILS :(

Ok from what you said and my 3 questions
Answer to question 1 should be that the lights are ONLY where there is ILS but they should work automatically no need to set anything up
Answer to question 2 the lights only work at an airport that has ILS
Answer to question 3 Not yet answered

Hopefully more people can weigh in :) Thank you for your help.
Last edited by Styggron on 03 Oct 2016, 02:17, edited 1 time in total.
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guillaume78150
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Re: How to use the O/M/I marker lights.

Post by guillaume78150 »

There must be a "Marker" switch somewhere on the "audio" panel of the instrument panel.
Unless I'm wrong, the O/M is linked with ILS frequency. If not on the right frequency, it won't light nor sound.
In zero conditions, it gives you the accurate position on the localizer.
Not all ILS approach offer three markers, sometimes, only the outer one is present.

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Styggron
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Re: How to use the O/M/I marker lights.

Post by Styggron »

guillaume78150 wrote:There must be a "Marker" switch somewhere on the "audio" panel of the instrument panel.
Unless I'm wrong, the O/M is linked with ILS frequency. If not on the right frequency, it won't light nor sound.
In zero conditions, it gives you the accurate position on the localizer.
Not all ILS approach offer three markers, sometimes, only the outer one is present.
Thank you for that.
Ok now we have two contradicting posts. One says they are not tired to the frequency and are automatic and this post says there is a marker switch on the audio panel and it might be linked to ILS

Ok I was 35 nm from EGPE, I tuned to the ILS frequency (although I was of course too far at that stage) and I pressed the marker on the audio panel marked MKR).
I did my ILS approach not a single light went on, no O or M or I and also NO sounds even though the MKR was pressed on the annunciator panel. :(

They never seem to on the default C172 or the B377.
Thank you for that. Lets see what more people say.

:)
Last edited by Styggron on 03 Oct 2016, 03:14, edited 4 times in total.
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guillaume78150
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Re: How to use the O/M/I marker lights.

Post by guillaume78150 »

It will light up anyway (provided you set the correct ILS frequency). Sound is switched on/off on the audio panel.

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Welsch
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Re: How to use the O/M/I marker lights.

Post by Welsch »

As far as i know, the transmitting frequency is fixed for these marker beacons, so no tuning of frequencies involved. If marker beacons are present (usually on ILS approaches - and almost everywhere when using OrbX scenery, they totally love marker beacons for some reason), and you fly over them, the corresponding lights will come on, simple as that.
And as Guillaume already explained, to also hear them the marker switch in the audio panel has to be active.

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Great Ozzie
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Re: How to use the O/M/I marker lights.

Post by Great Ozzie »

Styggron wrote: Ok from what you said and my 3 questions
Answer to question 1 should be that the lights are ONLY where there is ILS but they should work automatically no need to set anything up
Answer to question 2 the lights only work at an airport that has ILS
Answer to question 3 Not yet answered
Not exactly what I said.

Marker beacons light up where there are marker beacons.

The AIM reference would have taken you all of 30 seconds to read. To look up the other 3 terms - maybe another 60 seconds. And it would have clarified things a bit.
Welsch wrote:As far as i know, the transmitting frequency is fixed for these marker beacons, so no tuning of frequencies involved. If marker beacons are present (usually on ILS approaches - and almost everywhere when using OrbX scenery, they totally love marker beacons for some reason), and you fly over them, the corresponding lights will come on, simple as that.
Correct.

Btw Welsch, I know Nick posted on this at Orbx. What a mess. I would have hoped they straightened it out by now.
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guillaume78150
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Re: How to use the O/M/I marker lights.

Post by guillaume78150 »

I'm wrong :D
The "Marker" is a 75MHz receiver which works independantly from the other radio equipment.
As long as the aircraft is equipped, once on the vertical of the corresponding marker, it will light up and beep.

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bobsk8
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Re: How to use the O/M/I marker lights.

Post by bobsk8 »

Marker beacons are gradually being phased out.
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AKar
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Re: How to use the O/M/I marker lights.

Post by AKar »

Great Ozzie wrote:
Welsch wrote:(usually on ILS approaches - and almost everywhere when using OrbX scenery, they totally love marker beacons for some reason)
Btw Welsch, I know Nick posted on this at Orbx. What a mess. I would have hoped they straightened it out by now.
This issue only affects some of, or maybe the most of, their region products and also addon airport products (!!), which for some strange reason use significantly out-of-date or wrong aeronautical information. The airport runway data and terminal navaids are very often off, and as mentioned, the markers are everywhere. It is especially annoying, because there are tools to bring the FSX/P3D default aeronautical database up-to-date very easily, but these updates are locally overridden by the regions' updated airfield AFCADs.

Highly annoying problem, making a dent in the score of the regions in my eyes, as they are otherwise so nicely put together.

-Esa

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Great Ozzie
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Re: How to use the O/M/I marker lights.

Post by Great Ozzie »

AKar wrote:This issue only affects some of, or maybe the most of, their region products and also addon airport products (!!), which for some strange reason use significantly out-of-date or wrong aeronautical information.
I've just seen this in NCA (how I hope it is not worse than this!). And it seems like they just added all beacons (OM/MM/IM/BC) to essentially all runways. I noticed some military fields escaped this treatment. Doesn't look like any database was used at all. :roll:
Styggron wrote: Ok I was 35 nm from EGPE
I looked at EGPE - didn't see any marker beacons there.
Styggron wrote:They never seem to on the default C172 or the B377.
Park youself at KIND with C172. If you look at the Map - off the approach end of 5L and 5R, both runways have marker beacons for the OM, MM, and IM. You could fly off of either 23L or 23R and see the White / Amber / Blue lights illuminate. Just be sure to have pressed the MKR button so that the green annunciator bar is illuminated to hear the different marker sounds.
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Styggron
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Re: How to use the O/M/I marker lights.

Post by Styggron »

Ok so in summary

1. the lights light up automatically no need to set anything. If you want to hear the beeps press the MKR on the annunciator panel
2. not all airports have it and EGPE do not have it.

Next question:
What do I look for on the chart to see if it has the markers ? I read EGPH has markers but I can't see anything on the chart. http://www.ead.eurocontrol.int/eadbasic ... -03-06.pdf
I looked at the Gen 2.3 sumbol Great Ozzie told me to see what is labelled as the OMI but found nothing :(


PS Great Ozzie. I spent a bit of time on the 726 document, reading the section you suggested. I still found it difficult I fear. I need easier more to the point succinct direct steps I fear :) Good background info though.

Thanks everyone. :)

PS: I also checked this out. http://www.navfltsm.addr.com/ils.htm
Last edited by Styggron on 03 Oct 2016, 19:21, edited 1 time in total.
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Styggron
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Re: How to use the O/M/I marker lights.

Post by Styggron »

Great Ozzie wrote:
AKar wrote:This issue only affects some of, or maybe the most of, their region products and also addon airport products (!!), which for some strange reason use significantly out-of-date or wrong aeronautical information.
I've just seen this in NCA (how I hope it is not worse than this!). And it seems like they just added all beacons (OM/MM/IM/BC) to essentially all runways. I noticed some military fields escaped this treatment. Doesn't look like any database was used at all. :roll:
Styggron wrote: Ok I was 35 nm from EGPE
I looked at EGPE - didn't see any marker beacons there.
Styggron wrote:They never seem to on the default C172 or the B377.
Park youself at KIND with C172. If you look at the Map - off the approach end of 5L and 5R, both runways have marker beacons for the OM, MM, and IM. You could fly off of either 23L or 23R and see the White / Amber / Blue lights illuminate. Just be sure to have pressed the MKR button so that the green annunciator bar is illuminated to hear the different marker sounds.
I looked at the KIND map, I see no OM,MM,IM markers on there http://flightaware.com/resources/airpor ... WY+05L/pdf and nothing on this map either http://flightaware.com/resources/airpor ... III%29/pdf

I checked a few UK maps as this is where I fly, never seen anything I can ID as OMI marking :(


:(
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Re: How to use the O/M/I marker lights.

Post by Oracle427 »

The thing shaped like an eye with a shaded interior that has "IM" next to it is the inner marker.

In the profile view of the approach you can see IM along path just before the runway.
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