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Loggings => Longwave Loggings => Topic started by: Bernhard on October 31, 2021, 1114 UTC

Title: Only few NDBs in Europe, are they mostly shut down?
Post by: Bernhard on October 31, 2021, 1114 UTC

here in Berlin/Germany I recently noticed that our local NDBs like 299 "SL" and 309 "MW" are gone and also the whole band is very quiet. I managed to hear only very few signals the last few nights:

307 DIK from Luxembourg
346 WLU from Luxembourg
347 CVT from France
370 GAC from Bosnia-Herzegovina
372 ODR from Norway

I read about a "Phase 6" decommissioning in Canada, what about other parts of the world, will they all be shut down in the near future?
Title: Re: Only few NDBs in Europe, are they mostly shut down?
Post by: skeezix on October 31, 2021, 1517 UTC

Here in the U.S., the NDBs are also going away. The FAA 2018 Navigation Programs Strategy (https://www.aopa.org/-/media/Files/AOPA/Home/Advocacy/Advocacy/Advocacy-Briefs/Navigation_Programs_Strategy_2018_Final.pdf) (5.3, p19) has some information for the NDBs.

5.3 Non-Directional Beacon (NDB)
NDBs, as shown in Figure 11, are transmitters that pilots can use with avionic direction-finding equipment (typically a receiver with a steerable loop antenna) to determine the azimuth of the aircraft to the NDB ground station. NDBs serve as non-precision approach aids at some airports; as compass locators, generally collocated with the outer marker of an ILS, to assist pilots in determining the step down fix to begin the descent to the Decision Altitude (DA) on the ILS course in a non-radar environment; and as en-route navigation aids. By determining the azimuth to at least two NDBs, a pilot can determine the aircraft position. Historically, NDBs were collocated with the Outer Marker (OM) and Middle Marker (MM), which changed their designation to a Locator Outer Marker (LOM) and Locator Middle Marker (LMM). LOM and LMM services have mostly been discontinued with the introduction of radar capabilities in terminal areas, but they are still used in non-radar areas in the NAS. The FAA still operates and maintains approximately 200 NDBs in Alaska.

All the current NDBs are beyond their 20-year service life.

5.3.1 NDB Sustainment
There is no FAA procurement activity for NDBs at this time. NDBs are being gradually phased out of the NAS. No additional NDB approaches will be published, and NDB approaches used for training by the DoD or private entities will not be included in the NAS. By 2030, all NDB approaches are expected to be removed from the NAS.

Here in the upper Midwest of the U.S. (Minnesota, Wisconsin, North Dakota, South Dakota, Iowa), many NDBs have disappeared with only a few remaining.

Canada is well under way in their NAVAID Modernization Program (https://www.navcanada.ca/en/air-traffic/navaid-modernization-program.aspx). As you correctly state, they're currently in Phase 6 of 12. Phase 7 is coming up in January.

Title: Re: Only few NDBs in Europe, are they mostly shut down?
Post by: pinto vortando on November 01, 2021, 0041 UTC
Can think of 20 or so U.S. and Canadian beacons formerly regularly heard here that have gone dark over the past few years.
Title: Re: Only few NDBs in Europe, are they mostly shut down?
Post by: liduck on November 02, 2021, 0847 UTC
Facebook has a group called Non Directional Beacon chat, and on it a gent regularly posts the NOTAMS about decommissioned US beacons, there's a least one a day.  We did have a bunch in my neck of the woods (Long Island) but are now down to 2.  There's also a group of NDB listeners who have a running list of what's heard and can be found here: http://www.ndblist.info/
Title: Re: Only few NDBs in Europe, are they mostly shut down?
Post by: Nick B. on November 21, 2021, 1535 UTC
Here in the UK, a lot of the en-route NDBs have disappeared although there are still a number at regional airports, as well as at RAF (military) airfields. In other parts of the world they are still in common use on the helicopter platforms of oil rigs.

In the UK the tone used for the Morse ID is 400Hz. The odd one is CWL on 423kHz which I have logged using 1020Hz.