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Any reason NOT to remove an ADF than has gone u/s?

The Jeppesen database for the GNS430W has the GPS overlay for the LDLO NDB approach.

Can you post a photo? Does it include the curved track?

Administrator
Shoreham EGKA, United Kingdom

There are many RNAV SIDs and STARs.

I would be keen to hear about the approved NDB (GPS) approaches chflyer tells us about. They would be a real boon. What we really need is NDB (GPS) + V.

EGKB Biggin Hill

A GPS overlay is different. A GPS can include the procedure coded. An overlay is an official GPS overlay procedure which effectively repalces the original for those suitably GPS equipped.

EGTK Oxford

OK here’s another data point. I know a pilot in Switzerland who did his IR test about 3 years ago. He said he was expected to fly NDB approaches using the GPS. This is non-JAA/non-EASA but Switzerland can do that because it is not in the EU. Chflyer is Swiss too.

Administrator
Shoreham EGKA, United Kingdom

What on earth is taking them so long? Are they really suggesting that a GPS overlay approach is less precise or safe than an NDB? Honestly, if you were stuck in icing cloud going into Greenland at night, in a single with a coughing engine, with no alternatives, what would you rather do: fly the NDB approach or the internal GPS in your tablet?

I’d take the tablet/phone GPS 100 times out of a 100.

Last Edited by AdamFrisch at 18 Mar 00:40

Yes, LDLO is not an official GPS overlay, and there’s the warning that you are not allowed to use it for guidance. Have to check the details the next time I’m flying.

@Adam: I agree in general, but I’d be careful using a tablet for an approach in IMC. It does not have the integrity check a certfied GPS does. If the devices freezes or there’s a GPS outage you might not realize it.

If you think that the official stance on overlay approaches is odd, have a look at the reasoning for switching off the glidepath on LNAV/VNAV approaches in the UK.

It all stems from regulators being much more concerned with the risks of allowing things than about the risks of proscribing them. Until they can be redirected on that front, these obviously ridiculous anomalies will persist.

EGKB Biggin Hill

In the US, an overlay approach has “or GPS” in the title. All of the NDB and VOR approaches as well as the ILS approaches are in the GNS/GTN database, but all will display a message from a Lawyer “Not Approved for GPS, GPS guidance is for monitoring only. Activate approach?” before you activate the procedure. The only approaches that don’t make it into the database are a few that can’t be coded in an ARINC database (DME arc all the way to the runway) or some that use RF legs and all RNAV (RNP) procedures which are Authorization Required.

There used to be more than 1000 overlays in the US, but most or all are now gone when RNAV (GPS) approaches are published at an airport. There are only 82 stand alone GPS approaches left in the US and most of them will go away.

KUZA, United States

EHLE has only NDB or NDB/DME approaches to both runways (05/23) and I always fly it on the GPS and do not use the ADF as primary source.

EDLE, Netherlands
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