NDB problems

Hey y’all!

I seem to be doing something wrong with NDBs.

  • Simulation: X-Plane 11 current version
  • Plane: Ddenn’s Challenger 300

Unfortunately I don’t have the manual on this particular glass cockpit. I am not even sure how it is called but it is one of the default ones of Xplane I think. I am not even sure there is a manual…

Here is a picture (ignore the frequencies, that’s from another flight):

I figured out most of the functionality by now but NDBs elude me.

I thought it would be similar to VORs, which are pretty easy:
I just dial them in in NAV1 or NAV2 (either using the FMC or by clicking on the frequency on the PFD screen).
Then I use the NAVSRC button to switch to them, and set the course using the FMC or the course knob.

Now, of course (pun intended) NDBs don’t transmit a distance or straight up tell me the direction like VOR/DMEs or TACAN, I can just home in on them. But they are supposed to have much greater range (unless they are marker beacons), which comes in handy. And Russia (where I am flying right now for the Christmas flight) doesn’t have a lot of VORs, but NDBs.

So here is what I tried:
I put in the frequencies, into ADF1 and ADF2.
There are some NDBs on the Skyvector map that I can input (for example IO, south of Murmansk, 1210 kHz), others don’t work (for example the ones near Naryan Mar, 680 kHz). The plane just adds a 1 so it changes the input to 1680.

But even for those that work, I couldn’t figure out how to let the plane use them. My available nav sources are just FMS, NAV1 and NAV2, which are GPS and VORs.

I figured that the plane maybe cannot use NDBs for the autopilot, so I tried this: set the AP to HDG and sync up the heading with the bearing to a beacon.
So I used the bearing source (BRGSRC) button and the menu button so put bearing source 1 and 2 to ADF.
I didn’t get a green bearing indicator though. :frowning:
I do get the green bearing indicators when I use VORs.

That’s where I am basically stuck.
I was definitely close enough for the NDB and it does exist in Xplane. I could see it on the glass cockpit’s map, and I passed it at a slant range of approximately 15 miles, if which most was my altitude (FL420).

Any ideas what I could be doing wrong?

Edit: oh, and when I put in the frequency and activate it by clicking below it, I can choose between OFF, ON, STBY, TEST, ANT and BFO. What do those mean? When to use which?


Here is a document that you might find useful…

Another point to note is that the NDB database in X-Plane is somewhat incomplete, and also the range you can pick them up seems much shorter than you can in the real world. Having said that, you should still be able to pick them up at a useful distance.

To my knowledge, on the Global (I don’t fly the Challenger 300), the ADF is nothing more than a bearing pointer, ie you can’t tie it into the NAV mode of the autopilot. I doubt the Challenger 300 is any different in that regard. In a modern jet, you would navigate to a NDB using the FMS/GPS. It is simply another waypoint in the database. When flying a NDB approach, you would use a FMS/GPS overlay, and just bring up an ADF bearing pointer to keep things legal, but the autopilot would actually just fly the course using GPS. If you insist on just using the NDB, then as you surmise, you have to fly it in HDG mode.

I have the Dden CL300. I’ll dig into it a bit this morning if I get a chance.


Yes, I’ve found the X-Plane NDBs to not have a very good (or realistic) range.


Just flying around in the Challenger, I forgot how nice it is. Pity it uses the default FMS, but other than that it is great.

I had the ADF bearing pointer working just fine at 10000ft. In my test, I picked up the BS (255) NDB just south of KAUS out to 27nm

I am not sure exactly how Laminar models the service volume for ground based navaids. There is a significant ‘cone of confusion’ above a NDB or VOR. I believe it is as high as a 50° angle for NDB’s. That makes the cone a pretty big area when you are at 42000ft and could be a big factor in you not being able to pick up the station. I also think that the NDB’s in X-Plane are under powered.


Thanks a lot, guys!
I am really a noob when it comes to civil planes. :smiley:

I’ll try again soon, I admit that I am still quite far away from understanding all functions of even this simplified glass cockpit.

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You are welcome… bottom line, in an aircraft like the Challenger 300, you wouldn’t be navigating using raw data NDB’s and VOR’s unless you were having a bad day.


Yeah, I know. :slight_smile:
This is mostly academic, I want to know all the functions of the aircraft.

I have found that a letter substitution method works. For the letter N, substitute the letter G; for D substitute P; replace B with S. Problem solved :wink:


Those 2 letters together are pretty much how I live my life :joy::joy:

My process during the Air Race was this:

  1. Tune the frequency on the ADF;
  2. Turn on the audio for that ADF so I could tell when I was in range (and I might miss the ADF needle deflection once the signal is acquired);
  3. Once the needle deflects, it will point to the NDB. Adjust the ADF outer ring or not, depending on the module: the Duchess requires that you rotate the outer ring to match your compass heading to get a good reading on the ADF direction but the Bonanza does this for you;
  4. Turn to that heading to approach the NDB, or away to, you know, go away from it :-);
  5. Ranges can be really short but an flight planner (such as LittleNavMap) will ready the X-Plane DB and allow you to turn the ranges on, giving you some idea how long you may be out of signal range;

The Velocity V-Twin does not seem to have any ADF radios. I should try inputting one of the NDB frequencies into the Nav1/Nav2 radios to see if it will accept them but the dials do not allow me to get into the NDB frequency range (I seem limited to VOR/ILS frequncies).

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