What does all these mean?

I always wondered how to use these features and also what does BRG 1/2, CRS, ADF mean ?

I already know the use of SOURCE & MAP RANGE…can anyone please explain me the rest of the items ?

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Here’s an example for a use case. Generally, look around the “Take-Off to Cruise” section of the flying guide to get a few use cases and explanations!

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CRS 1 & CRS 2 are for setting the course deviation indicator (CDI) which is used when the source is NAV 1 or NAV 2. If source is NAV 1 it will track CRS 1, if NAV 2 it will track CRS 2. Mostly you will just use these when you are tracking a localiser and the system will automatically set the CDI course for you. But you can also use them when tracking a VOR. Most of the time we use GPS courses though. If you want to try it out though, set your self up to the south of a VOR and tune the VOR to say NAV 2, and select Source to NAV 2. Set CRS 2 to 360. You will see the CDI moving around as you select it. I won’t go into a full description of how to use it but basically if you are to the south of the VOR and you want to fly to it, if you set the CDI so that the needle centres and then fly on that track to the VOR you will maintain the same course all the way there.

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BRG 1 & BRG 2 are for the needle selections on your HSI. When you tune a VOR/ILS/NDB a needle will show up pointing to the station (VOR/ILS/NDB), although in real life they won’t point to an ILS. These buttons tell the system which station you want the needle to display. Using the example above, if you keep the needle pointed at the station you will fly over the station and the needle will then point behind you as you go over the top. Good navigation using this system requires you to use any necessary crab angle into the wind so that a constant track to the station is maintained. If you want to practise with this system, try and navigate to a station with strong winds. It’s not as easy as it looks! The trick is to remember that the needle always falls. I can describe that more if there’s any interest but getting a bit complicated now…

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And the NAV 1, NAV 2 & ADF 1 boxes at the top just show you which frequencies you have tuned at the moment.

The COMPASS NAV button is used to select how you have navigation data presented in the cockpit on the MFD. Typically ARC is used but NAV can also be used when navigating around VORs or for planning a route. If you use ARC you can set your range so that you have meaningful data for the phase of flight. For example at takeoff it’s common to have 20 miles or 40 miles range used so that thunderstorms and other traffic can be easily seen… At longer ranges the resolution is poor.

Hope that helps. Apologies if I have made it sound too complicated. Happy to elaborate if needed…

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Thanks a lot for the link !! I’ll look over it :)

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Thanks a lot for explaining everything…and yes I’d like you to elaborate as I’m a geek so I’d love to know more and don’t worry it’s not much complicated as I have at least intermediate knowledge of navigation and stuff…just was a bit confused with these buttons !!

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Ok no problems! Is there anything specific you would like me to elaborate on? The two areas that I could have gone further on are navigation using a VOR and HSI (Horizontal Situation Indicator), and navigation using an NDB. I can’t say I have read through the reference material. Perhaps there are good examples in there. And for what it’s worth, in IF the range of VORs, NDBs, and localisers appears to be infinite. If you tune them in the system picks up the nearest signal for that frequency (there are more VOR’s/ILSs/NDBs than available frequencies so there are many instances of stations with the same frequency as another somewhere else in the world) and shows data for that. In real life these navigation aids all have distance limitations on them. You can’t legally use them beyond a certain range.

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Looks like good material Avio. Thanks for posting MxP. You should have all you need for navigation there Avio…

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Ohh that’s something I didn’t know…Btw I’d like you to elaborate on NDB !!

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Sure thing…I am going through the material provided by @MxP !! Finding it really useful…thanks both of you guys for reaching out !! <3

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This may also help in addition to the link shared above.

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Wow…thanks a lot !! :)

Not sure where to start, but NDB’s are the most basic of navigation radio beacons used today. Occasionally you will see pictures of WWII aircraft with a large-ish round hoop on top of their fuselage. This was used for homing to a station. NDB’s are the same thing and use AM frequencies that are close to the radio stations we listen to. So it’s possible to listen to the radio if you want to using your ADF (the radio in the cockpit we use to tune NDB frequencies). Perhaps not the most professional thing to do with passengers on board though! Often used to listen out for the latest sport scores so they can be passed onto passengers.

As mentioned, to navigate to an NDB we use the needle pointing to the station to take us there. It’s quite basic. If the wind is blowing across us though, and we just keep the needle pointed at the station we will actually end up flying in a spiral to the station. That is, the heading to the station will change as the wind blows us to the side. To account for this the idea is to set up the correct crab angle into wind so that the bearing to the NDB station never changes.Say you have 10 degrees crab to the right because of wind from the right and you are trying to fly north to a station, you would want the needle pointing to 360 and your heading on 010. If the needle starts to move to say 355 it means that you have too much crab angle in and you have drifted to the right of the northerly course. Similarly if the needle moves to say 005 it means the wind has pushed you across and you need more crab angle to stay on course. To correct, the general rule is double your angle of error and correct by that much. It might not work so well if you are close into the station though.

As you approach the station the needle will get quite sensitive so you need to just fly the course until you fly over the top and it is now behind you. Once it’s behind you it’s the same sort of thinking to stay on track. Keep the needle on the desired course by using crab angle and make connections as needed.

In real life the signal from NDB’s can be quite wafty so they move around a bit, particularly when far out. You have to use a bit of judgment. It’s true though that NDB’s are used very rarely these days. If you want to give your NDB navigation a workout, try doing an NDB approach at an airport somewhere. You’ll need charts for this of course but it’s quite satisfying to fly well. There is a site somewhere that you can get charts for sim flying… Can’t remember its name though.

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Is the reverse possible ? I mean my car has AM/FM and some other mode…if I tune into AM at a right frequency is it possible for me to hear things happening on that frequency ? Like hearing to ATC on a VHF ?

Btw thanks a lot for providing me an in-depth info on this NDB thing…it’s really helpful and I’ll surely fly using charts and I’m excited to do it ;)

No the AM spectrum in your car radio is adjacent to the one used by aircraft so you can’t hear what’s going on in aviation world. Aircraft can tune their ADF across both aviation and consumer spectrums. You can however buy scanners I think that listen to aviation traffic. You can also go and have a look at liveatc.net if you want to hear real life ATC chatter.

For what it’s worth the spectrum of VHF frequencies used in aircraft for communications and navigation (VOR/ILS) are also adjacent to the FM band used by consumers, but unlike the ADF, we can’t tune the consumer band in the aircraft using aircraft radios. Although VHF is typically a line of sight frequency, there is a phenomenon known as atmospheric bounce where if the condtions are just so, a transmission on the other side of the world can bounce off the stratosphere to be received clear as day. I had that happen to me once and it was very odd. I was in Australia and was picking up a transmission in Africa. Didn’t last long though.

If you want to get really detailed, you can find the full use of the radio spectra on government websites, where they publish the different frequencies bands and which industry sectors they are reserved for. There’s a lot of competition for bandwidth and occasionally it gets ugly. Check the Federal Communication Commission in the US, Ofcom in the UK, and here’s a link for the one in Australia. They are generally the same across different countries.

HF is another topic altogether. Not used for navigation, only for communication. You feel like you are trying to tune in the aliens when you are talking on HF, such is the amount of noise and static usually. Can be quite distracting having all the static noise going on, so airliners use a system to basically keep that radio turned off unless someone dials in a specific code which is picked up by the HF radio in the cockpit. Known as SELCAL and used mostly on ocean crossnigs when out of VHF range.

Right. Enough from me! Hope that’s interesting…

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That’s so much interesting !! I loved to know about it…Thanks a lot :)

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