Shutting down NDBs

lancie00 said:
Still have one in our plane, at least until I can afford GPS. I use it regularly as we have an NDB as an outer marker on an ILS.
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My ADF's not coming out until it fails and isn't economically repairable. The Canada Flight Supplement (our A&FD) still publishes the lat/lon of commercial AM radio stations, and that's my goto if all else fails: GPS blocked because of a threatened terror attack, stuck too low under an icing layer to get VOR reception, etc. Those 50,000 watt commercial AM transmitters won't give you high course precision (the track will be a bit of a slalom course), but they're not line-of-sight, so you can pick them up from huge distances at low altitude, unlike VOR.
 
Also (while this isn't as big a deal in the GPS and cheap-AHRS age), when you're flying straight towards an NDB after a vacuum failure, the ADF needle will give you a more-stable heading-deviation than you'll get from the whiskey compass, especially in turbulence. The VOR provides zero heading support, just course deviation.
 
My guess is that most NDB get pulled out by private pilots who own their airplanes just right before their IFR check-rides. I have know several pilots that have done this. Their thought, it is one less thing that they need to know that can cause them to fail their check-ride.
 
ahypnoz said:
My guess is that most NDB get pulled out by private pilots who own their airplanes just right before their IFR check-rides. I have know several pilots that have done this. Their thought, it is one less thing that they need to know that can cause them to fail their check-ride.
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On my IFR check ride the DPE asked if I practiced NDB approaches. I said no and he asked if I wanted to try one. I said sure, why not. Flew one with the help of Garmin pilot and circled to land. Worked well and was really pretty easy.
 
wsuffa said:
So, as things stand today, you'll find 50 KW to be the maximum power level on all channels in the US & Canada except the local channels, with the locals at 1 KW.
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It's a bit more complex than that...the "expanded band" (1610 to 1700kHz) is limited to 10kW.
 
ahypnoz said:
My guess is that most NDB get pulled out by private pilots who own their airplanes just right before their IFR check-rides. I have know several pilots that have done this. Their thought, it is one less thing that they need to know that can cause them to fail their check-ride.
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So sad that they thought that. I suspect it's because their instructors weren't competent to teach it in the first place, and passed their fear onto their students.

I loved NDB holds and approaches during my IFR training (2003), because they were so simple. You didn't have to keep changing the VOR radial, hoping you'd finish a turn in time before the CDI centred, etc. etc.
 
David Megginson said:
So sad that they thought that. I suspect it's because their instructors weren't competent to teach it in the first place, and passed their fear onto their students.

I loved NDB holds and approaches during my IFR training (2003), because they were so simple. You didn't have to keep changing the VOR radial, hoping you'd finish a turn in time before the CDI centred, etc. etc.
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Mine was intermittently flaky so I pulled it before instrument ride rather than take the chance of having it crap out. One less thing to worry about.
 
donjohnston said:
That's an AM radio station. It is my understanding that AM radio stations are not NDB's. While the ADF receiver on an aircraft can pick up AM radio stations, they aren't navaids.

But I could be wrong.
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They are VFR navaids, but not IFR.

Brad W said:
This old codger for one kinda hates to read this.
I certainly wouldn't want to have NDB's be the primary nav aid for everything....
but I value the simplicity of them.

Just speculating, VOR stations are probably much more complex and expensive to maintain....so I get the idea of letting them die out...but NDB's sure seem very basic and probably very cheap...and a network of them around seems like a great back-up in my thinking
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My understanding is that Canada is actually modestly expanding NDBs as they do their own MON-style VOR pull down.

smv said:
There are many airports around the country with only two types of approaches: NDB and RNAV. Take away the NDB and without an IFR certified GPS (yah, believe it or not, not every IFR airplane has an IFR GPS), you are not getting in....
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There are quite a few planes that don't have GPS, but do have VORs.

David Megginson said:
In Canada, if both your main destination and your alternate have only RNAV approaches, they have to be at least 100 nm apart (in most of the country). That's a serious operational issue for small planes with limited ranges. I'm not sure if there's any similar rule in the US.

Having a usable NDB or VOR approach at either the destination or the alternate removes the 100 nm restriction.
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Is that true if you are flying with WAAS?

Rgbeard said:
At Ensenada (MMES) the NDB transmitter was taken by thieves (copper?) and hasn't been replaced.

Unfortunately, it's the only instrument approach, and yeah, we get IMC here.
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I'm surprised they haven't done, at least, an RNAV/GPS.
 
smv said:
Wow...

5 Dec 2019
Shutdown SIDNEY NDB
30 Jan 2020
Delete BROADUS NDB
Delete CIRCLE NDB
Delete JORDAN NDB
Delete MALTA NDB
Delete PLENTYWOOD NDB
Delete ROUNDUP NDB

Pretty much "cleans up" all of eastern Montana.
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They still make great GPS waypoints.
 
donjohnston said:
What else could you use an NDB for?
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Old music and talk radio.
I did NDB approaches in 2003-2004 and they were good practice, but much less precise that VOR, especially in windy conditions where you're tracking a radial and not trying to hold a bearing. However, the reality if that in the US, they are dropping like flies. Does anyone want to bring back the 4 course range?

Search (Four Course Range) to see the video on YouTube.
 
Once again, you're referring to an AM radio station. I know that an ADF can pick up AM radio stations. That was addressed in post #24.

IMO, an NDB is a transmitter at a known location. If you don't know where it is, then it's not a navaid. If it's not on an official chart, then it's location is not really known. I haven't seen an AM radio transmitter on an aeronautical chart in a long time. Tuning in WGN on your ADF does not make it a NavAid any more than flying direct to your airfield using a GPS makes it an instrument approach.

From Southern Avionics:
"An NDB or Non-Directional Beacon is a ground-based, low frequency radio transmitter used as an instrument approach for airports and offshore platforms."

Wikipedia:
A non-directional (radio) beacon (NDB) is a radio transmitter at a known location, used as an aviation or marine navigational aid.

The list goes on.
 
donjohnston said:
Once again, you're referring to an AM radio station. I know that an ADF can pick up AM radio stations. That was addressed in post #24.

IMO, an NDB is a transmitter at a known location. If you don't know where it is, then it's not a navaid. If it's not on an official chart, then it's location is not really known. I haven't seen an AM radio transmitter on an aeronautical chart in a long time. Tuning in WGN on your ADF does not make it a NavAid any more than flying direct to your airfield using a GPS makes it an instrument approach.

From Southern Avionics:
"An NDB or Non-Directional Beacon is a ground-based, low frequency radio transmitter used as an instrument approach for airports and offshore platforms."

Wikipedia:
A non-directional (radio) beacon (NDB) is a radio transmitter at a known location, used as an aviation or marine navigational aid.

The list goes on.
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I can find the precise LAT/LON of any AM radio station in the United States:

https://wireless2.fcc.gov/UlsApp/AsrSearch/asrRegistrationSearch.jsp
 
Yep. And I can create an approach to an airport with no published instrument approach using a VOR or GPS or even an NDB. But that doesn't make it an instrument approach in the eyes of the FAA.
 
The known or unknown locations of AM radio stations is of little value in the modern context. Might be more productive to move on from this conversation.
 
Ryan F. said:
The known or unknown locations of AM radio stations is of little value in the modern context. Might be more productive to move on from this conversation.
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Yes sir!!
 
I think this has drifted a bit. No one is proposing using AM radio transmitters as primary IFR navigation; we're suggesting they could be a useful emergency backup in case the GPS system goes down and there's no VOR in range. AM transmitters aren't as accurate, but they're not limited to line-of-sight, and can have much longer ranges (especially at low altitude). Following one could get you into range of a VOR or localiser if you're stuck low beneath an icing layer, far from a VOR, when the sh*t hits the fan.
 
flyingbrit said:
WLW was 500kW only from 1934-1939. It is a "clear channel" and now has 50kW day and night.

There are several non-clear-channels with 50kW day and night. For example KMJ in Fresno, KBOI in Boise.
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I think KGO in San Francisco is a clear channel station. They do, however, run a 3 tower broadside array.

luvflyin said:
FCC may have, but Mexico didn't, you might hear this a thousand miles from the border from a 'Border Blaster' station after sundown

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I remember Wolfman Jack back in the "old days".

n2230b said:
LORAN was great. I’ve heard rumors that it’s coming back. Is it true LORAN is not subject to nuclear magnetic pulse damage/interference?
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Probably not coming back, but it sure worked. And I hated doing TEMPEST testing on Kodiak back in the late 1970s. You had to lift the headset off your ears when tuning past that Loran station. Otherwise it would life the cans off your ears for you.

I remember when the club had the Arrow, the ADF receiver in the panel really belonged in a museum. Analog tuning on that radio. It really wasn't useful for anything other than listening to a ball game when flying across the state.
 
David Megginson said:
No one is proposing using AM radio transmitters as primary IFR navigation; we're suggesting they could be a useful emergency backup in case the GPS system goes down
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earlier on I wasn't even proposing that... I was thinking how it might actually have made sense to maintain a network of low power actual NDB stations on airports....but piggybacking on commercial stations could make better sense in some ways!
 
I've sometimes envisioned an all-in-view receiver that uses a simple wide band quad antenna array that has an internal database of every known fixed transmitter(AWOS/ATIS, AM, FM, TV, VOR, NDB etc) and could pretty much figure out where you are in almost any conditions(at least in a 2d sense). Modern SDR seems to be making this an even more possible idea.
 
Pilawt said:
FAA needs to go back to charting AM broadcast stations on VFR charts.
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I have just completed a project to provide a KML overlay that can be used in Foreflight and other EFBSs which shows the location, frequencies, and call signs of all AM radio stations in the US. So you can turn the layer on, zoom in on a target area, and find nearby stations to use with your ADF (well, my plane still has one ;)

Available at my flying page at http://steinmetz.org/peter/flying/index.html.
 
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I once TERPed out a non-precision approach to my girlfriends house using a broadcast station as an NDB. It took three days just to guess on the data needed to create a legitimate approach. For some reason back then, it seemed fun.

The minima were raised if the porch light was OTS...
 
PeterNSteinmetz said:
I have just completed a project to provide a KML overlay that can be used in Foreflight and other EFBSs which shows the location, frequencies, and call signs of all AM radio stations in the US. So you can turn the layer on, zoom in on a target area, and find nearby stations to use with your ADF (well, my plane still has one ;)

Available at my flying page at http://steinmetz.org/peter/flying/index.html.
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That is neat.
 
Brad Z said:
This virus is powerful enough to take out 30 satellites 22,000 miles away in space, but spared every AM transmitter shack?
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Yup. LOL. :)

(Of course I’m joking around but the vulnerable part of GPS never was the satellites it’s the ground stations and the WAAS correction gathering and uplink sites and operators... if one is actually assessing real risks.)
 
denverpilot said:
Yup. LOL. :)

(Of course I’m joking around but the vulnerable part of GPS never was the satellites it’s the ground stations and the WAAS correction gathering and uplink sites and operators... if one is actually assessing real risks.)
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Yes, WAAS has ground stations, but un-augmented GPS doesn't. Obviously GPS has control stations on the ground, but I suspect as a DoD asset it's designed to continue to operate even if the control stations are taken offline, at least for a while...of course that's probably classified information.
 
Brad Z said:
Yes, WAAS has ground stations, but un-augmented GPS doesn't. Obviously GPS has control stations on the ground, but I suspect as a DoD asset it's designed to continue to operate even if the control stations are taken offline, at least for a while...of course that's probably classified information.
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But the signal is very, very weak and is easily overwhelmed by a relatively modest transmitter. Spoofed is harder, but to just take the GPS out? Pretty easy.
 
Brad Z said:
This virus is powerful enough to take out 30 satellites 22,000 miles away in space, but spared every AM transmitter shack?
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5,000 watts within 50 miles is quite hefty.
 
denverpilot said:
Yup. LOL. :)

(Of course I’m joking around but the vulnerable part of GPS never was the satellites it’s the ground stations and the WAAS correction gathering and uplink sites and operators... if one is actually assessing real risks.)
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The most vulnerable part of GPS is jamming the weak satellite signal with a stronger ground-based or airborne jamming transmitter. That's why the military has focused a lot of resources on GPS-denied environment (and what huge parts of the US are affected by the tests). There's also spoofing from ground-based transmitters.

And yes, it's been a problem. There were a couple of crackdowns that netted some truckers with such devices (to jam their logging and tracking systems) driving down a major interstate that runs next to a major international airport.
 
denverpilot said:
So we are all back to using NDB during the current zombie apocalypse, correct? Just checking. :)
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Fortunately, this isn't the kind of crisis that will affect the GPS network. But remember how, in September 2001, the U.S. wouldn't even let its own returning airliners enter U.S. airspace, so we had to let the trans-Atlantic (etc.) flights land in Canada before they ran out of fuel—your government will react hard and fast to any new kind of attack in progress, if <deity forbid> it ever happens at that scale again, and encrypting/shutting down/blocking GPS signals is an obvious early step in the fog of war at the start, when no one's sure what's happening.

There's no easy way to shut down every NDB and AM station centrally.
 
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You guys took my joke way too seriously. But I do miss listening to baseball when flying. :)
 
denverpilot said:
You guys took my joke way too seriously. But I do miss listening to baseball when flying. :)
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When I tune in commercial stations on my NDB, it's usually either shouty old talk radio hosts who want me to know that they're ANGRY ABOUT EVERYTHING!, classic country, or golden oldies from the 40s and 50s. I never manage to find the games. :(
 
David Megginson said:
When I tune in commercial stations on my NDB, it's usually either shouty old talk radio hosts who want me to know that they're ANGRY ABOUT EVERYTHING!, classic country, or golden oldies from the 40s and 50s. I never manage to find the games. :(
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I’ve actually thought of maybe enhancing the overlay map with some kind of format indicator in the description, but would need to find a database of that or some way to autoscrape the web.
 
Velocity173 said:
Well the Army has them at most of their active airfields so I’m sure they’ll keep them for awhile. All of their newest helos are still equipped with ADFs as well. Maintaining them is probably a drop in the bucket for their budget compared other things like PAR operating costs.

I’m sure deployment NDBs will become a thing of the past though, if they haven’t already.

View attachment 83140
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I could easily see the military keeping NDB's. A NDB transmitter would be cheap and mobile. Could easily drop one from most any aircraft. Would be a great back up for GPS.
Turning off GPS coverage for an area and using limited Time NDB signals could be very useful in some tactical situations.

Brian
 
brcase said:
I could easily see the military keeping NDB's. A NDB transmitter would be cheap and mobile. Could easily drop one from most any aircraft. Would be a great back up for GPS.
Turning off GPS coverage for an area and using limited Time NDB signals could be very useful in some tactical situations.

Brian
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Not NDB, but still an interesting bit of tactical radio nav history:

https://en.wikipedia.org/wiki/Battle_of_the_Beams
 
brcase said:
I could easily see the military keeping NDB's. A NDB transmitter would be cheap and mobile. Could easily drop one from most any aircraft. Would be a great back up for GPS.
Turning off GPS coverage for an area and using limited Time NDB signals could be very useful in some tactical situations.

Brian
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Tactical NDBs used to be common but over the years they’ve been reduced in number. Honestly don’t even remember a single tactical NDB approach in Afghanistan. It’s mostly using host nation approaches or tactically, emergency GPS approaches and tactical ATC (ATNAVICS).
 
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