Simviation Forums

That pretty much sums it up.  I have ADF radios that I don't have a clue as to what they do.  When I tune them in to an ADF frequency they don't do anything.  Do they serve any purpose?

"IF"  you are in range (NDB's have a pretty short range) the needle on the ADF gauge simply points "to" the transmitter.

If you disregard the heading ring (I usually do). The ADF pointer gives a relative bearing to the station. (left is left..up is front..down is back.. right is right..etc.)

If you turn the heading ring to match the heading you're flying (like you're supposed to).. the headind that the needle points to is the heading you need to fly, to fly "to" the station..

make sense ?

OK. I cranked up my C-172, which has an ADF gauge, tuned in an ADF frequency, and the gauge worked as predicted.

The range on this particular beacon was 40 miles and the beacon was in the middle of nowhere, as most of them seem to be.

Once I got close to the beacon I could see that I was passing it at different headings.

What possible use could I make of this information?

OK. I cranked up my C-172, which has an ADF gauge, tuned in an ADF frequency, and the gauge worked as predicted.

The range on this particular beacon was 40 miles and the beacon was in the middle of nowhere, as most of them seem to be.

Once I got close to the beacon I could see that I was passing it at different headings.

What possible use could I make of this information?

if you fly over the NDB, the arrow wants to point at it, so it turns around the whole scale, eventually pointing backwards

I think it's easier to go to the lessons and find the navigation section and look at what is there. A lot of it really does apply in flight planning and I use both VORs and NDBs(either or)depending on whether they are available or revert to map and compass VFR. That and a KANE DEAD RECKONING COMPUTER -no it's not a zip folder,it's a real life aviation calculator.

What possible use could I make of this information?

Ha!

You're obviously not an IFR flyer Jim!

One example. You enter the hold for approach to Kai Tak over VOR CH (Cheung Chau) at a height of say 12000 ft. The hold is fly to CH on hdg 270, o/hd CH turn left onto 090 and repeat. In the hold you descend to 6000 ready for your approach on the IGS to rwy 13.

You leave the hold at 6000 ft on 270 from CH. At waypoint Golf which is 7 nm DME from CH, NDB SL (Sha Lo Wan) bears 360 deg. You commence a descending right turn at Golf onto 45 deg to intercept the IGS.

So NDB SL is used to define waypoint Golf and is essential for an IFR approach especially in poor vis.

It's all in the Approach Chart. Why do it?   Because it's challenging and it's fun. There's much more to this sim than just faffing around in a 182 at 3500 ft I can tell you!



Roger

lol "faffing"  Like that!!

WebbPA,

Adding to what Rollerball stated about waypoints, Outer Marker NDB's are also essential for flying IFR.  If you look at a major airport in Map View,  you might see NDB's lined up with an approach path for a given runway, approximately 5nm from the field.   These are Outer Marker NDB's, and they are used as an aid for establishing the localizer for an ILS approach.  

Per Instrument Flight Rules, if you fly at a heading to intercept the localizer at an angle of 30 degrees, tuning the Outer Marker NDB for that runway will show you how close you are to intercepting the localizer.  As the needle approaches the runway heading, you can prepare to turn toward the runway.  I use it religiously when it's available!

Erik

Hi

Ok this is as simple as I am.

VOR stands for Very high frequency Omni Ranging.  And its exactly that it operates in the high freuquency bandwidth as you can tell when you tune you radio to a VOR frequency E.G. 111.1 Mhz (megahertz)  thats high frequency.  The signal can tell your instruments direction, height and ranging hense you can do an ILS approach.

NDB stands for Non-Directional Beacon.  And again it does what it says on the packet. These operate in the low frequency range 190 to 535 Khz (kilohertz) and all it will allow you to do is home in on the beacon, that is fly in a straight line towards it.

So look at the airport where you want to land, tune the VOR frequency to NAV1 and hopefully you'll see a NDB beacon on the approach line to the airstrip(but not always), tune this to the ADF and the combination of the two will hopefully fly straight onto the airfield.

Note not all NDB's are on the approach vector and are offset. (Before I get any mail.)

Please note I'm a novice and the accuracy of information given is on the understanding it could be completely pants and I'm sure fellow Flight Sims will put me right if it is.

Happy Landings
Phil

Wow, I didn't realize so many people actually knew how this worked.  I'm just going to save this whole post and print it for later reference.

Try this site out for navigation instruction.

http://www.navfltsm.addr.com/